In number theory , a semiperfectnumber or pseudoperfect number is a natural number n that is equal to the sum of all or some of its proper divisor s. A semiperfectnumber that is equal to the sum of all its proper divisors is a perfect number . The first few semiperfect numbers are 6 number 6 , 12 number 12 , 18 number 18 , 20 number 20 , 24 number 24 , 28 number 28 , 30 number 30 , 36 number 36 , 40 number 40 , ... OEIS id A005835 Properties Every multiple of a semiperfectnumber is semiperfect. A semiperfectnumber that is not divisible by any smaller semiperfectnumber is a primitive semiperfectnumber . Every number of the form 2 sup m sup p for a natural number m and a prime number p such that p 2 sup m 1 sup is also semiperfect. In particular, every number of the form 2 sup m 1 sup 2 sup m sup 1 is semiperfect, and indeed perfect if 2 sup m sup 1 is a Mersenne prime . The smallest odd semiperfectnumber is 945 see, e.g., Friedman 1993 . A semiperfectnumber is necessarily either perfect or abundant number abundant . An abundant number that is not semiperfect is called a weird number . With the exception of 2 , all primary pseudoperfect number s are semiperfect. Every practical number that is not a power of two is semiperfect. References cite journal title Sums of divisors and Egyptian fractions author Friedman, Charles N. journal Journal of Number Theory year 1993 volume 44 pages 328 339 url http dell5.ma.utexas.edu users friedman divisors.ps id MathSciNet id 1233293 doi 10.1006 jnth.1993.1057 issue 3 cite book author Guy, Richard K. authorlink Richard K. Guy title Unsolved Problems in Number Theory publisher Springer Verlag date 2004 isbn 0 387 20860 7 oclc 54611248 Section B2. cite journal author Sierpi ski, Wac aw title Sur les nombres pseudoparfaits language French ... PseudoperfectNumber title Pseudoperfect Number Divisor classes navbox Category Integer sequences ... semi parfait it Numero semi perfetto he nl Semiperfect getal ja ru ... more details
In number theory , a primitive semiperfectnumber also called a primitive pseudoperfect number , irreducible semiperfectnumber or irreducible pseudoperfect number is a semiperfectnumber that has no semiperfect proper divisor . The first few primitive semiperfect numbers are 6 number 6 , 20 number 20 , 28 number 28 , 88 number 88 , 104 number 104 , 272, 304, 350, ... OEIS A006036 There are infinitely many odd primitive semiperfect numbers the smallest is 945 , as well as infinitely many primitive semiperfect numbers that are not harmonic divisor number s. External links MathWorld urlname PrimitiveSemiperfectNumber title Primitive semiperfectnumber Divisor classes navbox Category Integer sequences eo Primitiva duonperfekta nombro fr Nombre semi parfait primitif it Numero semiperfetto primitivo ru zh ... more details
Merge to perfect ring date March 2011 In abstract algebra , a semiperfect ring is a ring mathematics ring over which every finitely generated module finitely generated left module mathematics module has a projective cover . This property is left right symmetric. Definition Let R be ring. Then R is semiperfect if any of the following equivalent conditions hold R J R is semisimple module semisimple and idempotent s lift modulo J R , where J R is the Jacobson radical of R . R has a complete orthogonal set e sub 1 sub , ..., e sub n sub of idempotent s with each e sub i sub R e sub i sub a local ring . Every simple module simple left right module mathematics R module has a projective cover . Every finitely generated module finitely generated left right R module has a projective cover . The category of finitely generated projective math R math modules is Krull Schmidt category Krull Schmidt . Examples Examples of semiperfect rings include Left right perfect ring s. Local ring s. Left right Artinian ring s. dimension vector space Finite dimensional algebra over a field k algebras . Properties Since a ring mathematics ring R is semiperfect iff every simple module simple left module mathematics R module has a projective cover , every ring mathematics ring Morita equivalence Morita equivalent to a semiperfect ring is also semiperfect. References cite book last Anderson first Frank Wylie coauthors Fuller, Kent R title Rings and Categories of Modules publisher Springer date 1992 isbn 0387978453 url http books.google.com books?id PswhrD wUIkC accessdate 2007 03 27 Category Ring theory Category Module theory de Semiperfekter Ring ... more details
In mathematics , a semiperfect magic cube is a magic cube that is not a perfect magic cube , i.e., a magic cube for which the cross section geometry cross section diagonals do not necessarily sum up to the cube s magic constant . combin stub Category Magic squares fr Cube magique semi parfait it Cubo magico semi perfetto ... more details
S number may refer to Meter Point Administration Number , often referred to as Supply Number or S Number, a 21 digit number used in Great Britain to uniquely identify electricity supply points S number wool , an international scale measuring the fineness of the threads in woven wool. Singular value , in mathematics, the square root of an eigenvalue of a nonnegative self adjoint operator. disambig ... more details
T number or T number may refer to A numerical system for the glyphs within the Pre Columbian Mayan script, see J. Eric S. Thompson . Dvorak technique , a system to subjectively estimate tropical cyclone intensity capsid T number Viral capsid T number , a system to describe the icosahedral surface quasi symmetry pattern In music, the transposition of a tone row disambig ... more details
A number is a mathematical object used to counting count and measurement measure . In mathematics , the definition of number has been extended over the years to include such numbers as 0 number zero , negative number s, rational number s, irrational number s, and complex number s. Mathematical operation ... a number as output. Unary operation s take a single input number and produce a single output number ... of 4 is 5. Binary operation s take two input numbers and produce a single output number. Examples of binary ... a number is called a Numeral system numeral . In addition to their use in counting and measuring, numerals are often used for labels telephone number s , for ordering serial number s , and for codes e.g., ISBN s . In common use, the word number can mean the abstract object, the symbol, or the numeral linguistics word for the number. Classification of numbers See also List of types of numbers ... sets , called number system s. For different methods of expressing numbers with symbols, such as the Roman ... 400px height 200px Important number systems math mathbb N math Natural 0, 1, 2, 3, 4, ... or 1, 2, 3 ... Natural number The most familiar numbers are the natural number s or counting numbers one, two, three ... a number for the Ancient Greeks . However, in the 19th century, set theory set theorists and other ... the smallest cardinal number in the set of natural numbers. citation needed date March 2011 Today .... In this base ten system, the rightmost digit of a natural number has a place value of one, and every ... of equivalent sets. For instance, the number 3 can be represented as the class of all sets that have exactly three elements. Alternatively, in Peano Arithmetic , the number 3 is represented as sss0 ... of symbols three times. Integers Main Integer The Negative number negative of a positive integer is defined as a number that produces zero when it is added to the corresponding positive integer ... de Zahl number . The set of integers forms a Ring mathematics ring with operations addition and multiplication ... more details
Infobox Play name A Number image image size caption writer Caryl Churchill chorus characters Salter br ... web playbill event ibdb id A Number is a 2002 play by English people English playwright Caryl Churchill ... years old. Contextual Information Caryl Churchill s A Number is an original work published in 2002 in London in association with the Royal Court Theatre. ref Churchill, Caryl. A Number. New York Theatre Communications Group, 2003. ref A Number was written when cloning was often in the news. Dolly ..., Georgina. A Number. Mail on Sunday London 29 Sept. 2002. ref Salter s action seem unreasonable, in the dialogue they say but another child might have been better ref Churchill, Caryl. A Number. New .... ref Churchill, Caryl. A Number. New York Theatre Communications Group, 2003. p. 51 ref He then turns ... is utterly baffling to the tormented Salter. . ref Jones, Oliver. A Number. What s On London ... a depth that Salter is searching for, but is content without it. Genre The genre of A Number would be considered a tragedy. The overall mood of tragedies is solemn, and the mood of A Number is certainly ... re not a unique person, but one of many, just a number. This story from a subjective position, though ... with the play itself, only observing. Language The use of language in A Number is unique and slightly ... inarticulate chat. ref Myerson, Jonathan. A Number. Independent London 1 Oct. 2002. ref This choice ... hand. ref name Jongh, Nicholas 2002 De Jongh, Nicholas. A Number. Evening Standard London 27 Sept. 2002. ref The rhythm that Churchill chose for A Number is a normal pace. The dialogue is just normal ... the best. ref Churchill, Caryl. A Number. New York Theatre Communications Group, 2003. p. 26 ref Staging ... Bernards usually wore jeans and a T shirt, but sometimes a sweatshirt. ref Basset, Kate. A Number ... Coyan. Adaptations A Number was adapted by Caryl Churchill for television, in a co production between ... 26197 70 title A Number work BBC Two Listings publisher BBC accessdate 2008 09 09 ref References Reflist ... more details
836 is the natural number following 835 and preceding 837. In mathematics 836 is a weird number . Its factorization is 2 sup 2 sup × 11 × 19, so its divisors are 2, 4, 11, 19, 22, 38, 44, 76, 209, and 418. They sum to 843. As this is greater than 836, it is an abundant number , but no subset sums to 836, so it is not a semiperfectnumber therefore it is weird. See also 836 year 836 Jole asteroid 836th Air Division , an inactive United States Air Force organization 836 Naval Air Squadron , a World War II organization in the British Navy Pi Arietis , designated as object 836 in the Bright Star catalogue Category Integers 89e02 836 ht 836 nonm ms 836 nombor ... more details
Dablink The term weird number also refers to Two s complement The most negative number a phenomenon in two s complement arithmetic . In number theory , a weird number is a natural number that is abundant number abundant but not semiperfectnumbersemiperfect . ref cite journal last Benkoski first Stan authorlink coauthors title E2308 in Problems and Solutions journal The American Mathematical Monthly volume 79 issue 7 page 774 date Aug. September 1972 doi 10.2307 2316276 jstor 2316276 ref ref cite book author Richard K. Guy authorlink Richard K. Guy title Unsolved Problems in Number Theory publisher Springer Verlag year 2004 isbn 0 387 20860 7 oclc 54611248 Section B2. ref In other words, the sum of the proper divisor s divisors including 1 but not itself of the number is greater than the number, but no subset of those divisors sums to the number itself. Examples The smallest weird number is 70. Its proper divisors are 1, 2, 5, 7, 10, 14, and 35 these sum to 74, but no subset of these sums to 70. The number 12, for example, is abundant but not weird, because the proper divisors of 12 are 1, 2, 3, 4, and 6, which sum to 16 but 2 4 6 12. The first few weird numbers are 70, 836, 4030, 5830, 7192, 7912, 9272, 10430, ... OEIS id A006037 . Properties It has been shown that an infinite number of weird numbers exist in fact, the sequence of weird numbers has positive asymptotic density . ref name benk1 cite journal last Benkoski first Stan authorlink coauthors Paul Erd s title On Weird ... , Journal of Number Theory 1993 . The result is attributed to M. Mossinghoff at University of Texas Austin . ref Stanley Kravitz has shown that if k is a positive integer, Q is a prime number prime , and math R frac 2 kQ Q 1 Q 1 2 k math if R is prime, then math n 2 k 1 QR math is a weird number ... 1976 ref With this formula, he was able to find a large weird number math n 2 56 cdot 2 61 1 cdot153722867280912929 ... title Weird number Portal Mathematics Divisor classes navbox DEFAULTSORT Weird Number Category ... more details
102 one hundred and two is the natural number following 101 number 101 and preceding 103 number 103 . Numbernumber 102 range 100s cardinal one hundred and two ordinal nd ordinal text one hundred and second numeral 102 factorization math 2 cdot 3 cdot 17 math prime divisor 1, 2, 3, 6, 17, 34, 51, 102 roman CII unicode greek prefix latin prefix bin 1100110 oct duo hex 66 misc In mathematics 102 is an abundant number and semiperfectnumber . It is a sphenic number . It is the sum of four consecutive prime numbers 19 23 29 31 . The sum of Euler s totient function x over the first eighteen integers is 102. 102 is the third base 10 polydivisible number , since 1 is divisible by 1, 10 is divisible by 2 and 102 is divisible by 3. This also shows that 102 is a Harshad number . In science The atomic number of nobelium , an actinide. In other fields 102 is also The emergency telephone number for police in Ukraine and Belarus The emergency telephone number for fire in Israel The emergency telephone number for ambulance in parts of India The Empire State Building in New York City has 102 floors See also List of highways numbered 102 References Wells, D. The Penguin Dictionary of Curious and Interesting Numbers London Penguin Group. 1987 133 Category Integers ar 102 az 102 d d ca Cent dos cv 102 eu Ehun eta bi fa fr 102 nombre gu ko 102 id 102 angka it 102 numero ht 102 nonm hu 102 sz m mk 102 ms 102 nombor nl 102 getal ja 102 no 102 tall pt Cento e dois ru 102 nso 102 nomoro simple 102 number sl 102 tevilo sv 102 tal th 102 uk 102 vi 102 s zh yue 102 zh 102 ... more details
For the Australian TV series see Number 96 TV series . For other uses see 96 disambiguation . 96 ninety six is the natural number following 95 number 95 and preceding 97 number 97 . Numbernumber 96 range 90s cardinal ninety six ordinal th ordinal text ninety sixth numeral 96 factorization math 2 5 cdot 3 math prime divisor 1, 2, 3, 4, 6, 8, 12, 16, 24, 32, 48, 96 roman XCVI unicode greek prefix latin prefix bin 1100000 oct 140 duo 80 hex 60 misc In mathematics Ninety six is an octagonal number , a refactorable number and an untouchable number . Since it is a multiple of 6, it is a semiperfectnumber Ninety six is the fourth Granville number and the second non perfect Granville number. The next Granville number is 126 number 126 , the previous being 24 number 24 . The sum of Euler s totient function x over the first seventeen integers is 96. Since it is possible to find sequences of 96 consecutive integers such that each inner member shares a factor with either the first or the last member, 96 is an Erd s Woods number . Every integer greater than 96 may be represented as a sum of distinct super prime numbers. See also List of highways numbered 96 External links Commons cat 96 number http www.wisdomportal.com Numbers 96.html On the number 96 DEFAULTSORT 96 Number Category Integers ab ar 96 az 96 d d bo ca Noranta sis cv 96 da 96 tal es Noventa y seis eo Na dek ses eu Laurogeita hamasei fa fr 96 nombre gan 96 ko 96 id 96 angka ia 96 numero it 96 numero ht 96 nonm lt 96 skai ius hu 96 sz m mk 96 ms 96 nombor nah N uhp hualcaxt lonc nl 96 getal ja 96 no 96 tall pnb 96 pl 96 liczba pt Noventa e seis ru 96 nso 96 nomoro sl 96 tevilo srn Numro 96 sv 96 tal th 96 uk 96 vi 96 s war 96 ihap zh yue 96 zh 96 ... more details
104 one hundred and four is the natural number following 103 number 103 and preceding 105 number 105 . Numbernumber 104 range 100s cardinal one hundred and four ordinal th ordinal text one hundred and fourth numeral 104 factorization math 2 3 cdot 13 math prime divisor 1, 2, 4, 8, 13, 26, 52, 104 roman CIV unicode greek prefix latin prefix bin 1101000 oct 150 duo 88 hex 68 misc In mathematics One hundred and four is a primitive semiperfectnumber and a composite number , with its divisor s being 1, 2, 4, 8, 13, 26, 52 and 104. As it has 8 divisors total, and 8 is one of those divisors, 104 is a refactorable number . The distinct prime factors of 104 add up to 15, and so do the ones of 105, hence the two numbers form a Ruth Aaron pair under the first definition. In regular geometry , 104 is the smallest number of unit line segments that can exist in a plane with four of them touching at every Vertex geometry vertex . In science The atomic number of rutherfordium . Number of degrees Fahrenheit corresponding to 40 Celsius. In other fields 104 is also The number of Corinthian columns in the Temple of Olympian Zeus , the largest temple ever built in Greece . The number of guns on Admiral Horatio Nelson s flagship HMS Victory . The number of Symphonies written by Joseph Haydn on which numbers are agreed upon though in fact, he wrote more see list of symphonies by Joseph Haydn . See also List of highways numbered 104 UFC 104 References Wells, D. The Penguin Dictionary of Curious and Interesting Numbers London Penguin Group. 1987 133 DEFAULTSORT 104 Number Category Integers ar 104 az 104 d d ca Cent quatre cv 104 eu Ehun eta lau fa fr 104 nombre ko 104 id 104 angka it 104 numero ht 104 nonm hu 104 sz m mk 104 ms 104 nombor nl 104 getal ja 104 no 104 tall pt Cento e quatro ru 104 nso 104 nomoro sl 104 tevilo sv 104 tal th 104 uk 104 vi 104 s zh yue 104 zh 104 ... more details
270 two hundred and seventy is the natural number following 269 number 269 and preceding 271. class wikitable width 250 style float right colspan 2 Numbers 200s Ordinal number Ordinal Two hundred and seventieth Cardinal number Cardinal Two hundred and seventy Factorization math 270 2 cdot 3 3 cdot 5 math Roman numeral CCLXX Binary numeral system Binary 100001110 Hexadecimal 10E In mathematics 270 is a harmonic divisor number 270 is the fourth number that is divisible by its average integer divisor OEIS id A007340 270 is a practical number , by the second definition The sum of the coprime counts for the first 29 integers is 270 270 is a sparsely totient number , the largest integer with 72 as its totient Given 6 elements, there are 270 square permutations OEIS2C id A003483 10 has 270 divisor s 270 is a Harshad number in base 10 270 is the smallest positive integer that has divisors ending by digits 1, 2, , 9. In other fields The year 270 BC The year 270 AD The caliber of the .270 Winchester rifle The number of Electoral College United States U.S. Electoral College votes needed to be President of the United States The average number of days in human pregnancy A pseudonym for Konami musician Naoki Maeda One of a number of secondary Interstate highways connecting to Interstate 70 Interstate ... hexagonal number , sum of eleven consecutive primes 7 11 13 17 19 23 29 31 37 41 43 . 272 Two hundred and seventy two 272 2 sup 4 sup 17, sum of four consecutive primes 61 67 71 73 , Euler number , primitive semiperfectnumber , pronic number 273 273 number Two hundred and seventy three has its own article. 274 Two hundred and seventy four 2 137, tribonacci number , Smith number , nontotient , noncototient , centered triangular number 275 Two hundred and seventy five 275 5 sup 2 sup 11 276 276 number Two hundred and seventy six has its own article. 277 Two hundred and seventy seven Perrin number , self number 278 Two hundred and seventy eight 278 2 139, nontotient 279 Two hundred and seventy ... more details
90 ninety is the natural number preceded by 89 number 89 and followed by 91 number 91 . Numbernumber 90 range 90s cardinal ninety ordinal th ordinal text ninetieth numeral 90 factorization math 2 cdot 3 2 cdot 5 math prime divisor 1, 2, 3, 5, 6, 9, 10, 15, 18, 30, 45, 90 roman XC unicode greek prefix latin prefix bin oct duo hex 5A misc Wiktionary ninety Image I 90.svg 100px thumb Interstate 90 is a freeway that runs from Washington state Washington to Massachusetts . In mathematics Because 90 is the sum of its unitary divisor s excluding itself , it is a unitary perfect number , and because it is equal to the sum of a subset of its divisors, it is a semiperfectnumber . 90 is a pronic number . But it is also a nontotient . It is a Perrin number , preceded in the sequence by 39, 51, 68. In normal space, the interior angles of a square measure 90 degrees each. Also, in a right triangle, the angle opposing the hypotenuse measures 90 degrees, with the other two angles adding up to 90 for a total of 180 number 180 degrees. ref http www.sparknotes.com testprep books newsat chapter20section4.rhtml http www.sparknotes.com testprep books newsat chapter20section4.rhtml ref Thus, an angle measuring 90 degrees is called a right angle. ref Friedman, Erich. http www.stetson.edu efriedma numbers.html What s Special About This Number? ref 90 is divisible by the sum of its base 10 digits, thus it is a Harshad number . In science Ninety is the atomic number of thorium , an actinide . As an atomic weight, 90 identifies an isotope of strontium , a by product of nuclear reactions including fallout ... 90 ft away in distance The car number most associated with former NASCAR team owner Junie Donlavey The number of minutes in a football soccer match. In Wellness Plans P90X is a rigorous work out plan ... DEFAULTSORT 90 Number Category Integers ab ar 90 az 90 d d bo ca Noranta ... tall nn Talet 90 pnb 90 pl 90 liczba pt Noventa ru 90 nso 90 nomoro scn Nuvanta simple 90 number ... more details
refimprove date December 2010 78 seventy eight is the natural number following 77 number 77 and followed by 79 number 79 . Numbernumber 78 range 70s cardinal seventy eight ordinal th ordinal text seventy eighth numeral 78 factorization math 2 cdot 3 cdot 13 math prime divisor 1, 2, 3, 6, 13, 26, 39, 78 roman LXXVIII unicode greek prefix latin prefix bin oct duo hex 4E misc In mathematics 78 is a triangular number , and its factorization makes it a sphenic number . As a multiple of a perfect number, 78 is itself a semiperfectnumber . 77 and 78 form a Ruth Aaron pair under the second definition in which repeated prime factors are counted as often as they occur. Since it is possible to find sequences of 78 consecutive integers such that each inner member shares a factor with either the first or the last member, 78 is an Erd s Woods number . Karl A. Dahlke proved in 1989 that 78 polyomino heptomino s of this shape Image heptomino 78.png , at a minimum, are required to fill a rectangle. In science The atomic number of platinum The number of chromosomes in canine DNA ref Both wolves and dogs possess 78 chromosomes. Handbook of Applied Dog Behavior and Training by Steven R. Lindsay, Wiley Blackwell 2000 p. 11 ref In other fields 78 is also In reference to gramophone record s, 78 refers those meant to be spun at 78 revolutions per minute . Compare gramophone record LP , Thirty three 33 1 3 and Forty five 45 rpm. 33 45 78 A typical tarot deck containing the 21 trump cards , the The Fool Tarot card Fool and the 56 suit cards make up 78 cards The total number of gifts in the song The Twelve Days of Christmas since 78 is the 12th triangular number The number of lines that make up Metatron s Cube fact date May 2010 The Rule of 78s is a method of yearly interest calculation fact date May 2010 Municipal Okrug 78 , a municipal okrug of Tsentralny District of St. Petersburg, Russia References references Category Integers ab ar 78 az 78 d d bo ca Setanta ... more details
totient number . 240 is a semiperfectnumber . 240 can be expressed as a sum of consecutive primes ...Unreferenced date December 2009 240 200 number two hundred and forty is the natural number following 239 number 239 and preceding 241 number 241 . border 1 style float right border collapse collapse colspan 2 Numbers 200s Cardinal number Cardinal two hundred and forty Ordinal number Ordinal two hundred ..., 15, 16, 20, 24, 30, 40, 48, 60, 80, 120, and 240 , more than any previous number, 240 is a highly composite number , and it is also a refactorable number or tau number, since it has 20 divisors and 20 ... of two consecutive integers, 15 and 16, thus 240 is a pronic number . Also, being divisible by the sum of its digits, 240 is a Harshad number , and not only that, it is also a concatenation of two ... before conversion to 230V standard. In British currency, the number of pence in a pound sterling pound until 1971. A cholesterol level of 240 and above is considered high risk. The model number ... comedy group The State TV series The State is entitled 240 Dollars Worth of Pudding 241 249 241 number Two hundred and forty one has its own article. 242 number Two hundred and forty two has its own article. 243 number Two hundred and forty three has its own article. Two hundred and forty four 244 2 sup 2 sup 61, nontotient, noncototient, self number . 245 number Two hundred and forty five has its own article. Two hundred and forty six 246 2 3 41, sphenic number , nontotient , untouchable number . Two hundred and forty seven 247 13 19, pentagonal number . br 247 50123 49876, and is the smallest number which can be expressed as the difference between two integers such that together, they contain ... 3 sup 31, nontotient, untouchable number, refactorable number E8 mathematics E sub 8 sub has complex dimension 248. The number 248 is also the Gematria value for the Hebrew letters Ramach Resh Mem and Het , traditionally depicted as the number of organs in the human body, and the number of positive ... more details
80 eighty is the natural number following 79 number 79 and preceding 81 number 81 . Numbernumber 80 range 80s cardinal eighty ordinal th ordinal text eightieth numeral 80 factorization math 2 4 cdot 5 math prime divisor 1, 2, 4, 5, 8, 10, 16, 20, 40, 80 roman LXXX unicode greek prefix latin prefix bin 1010000 oct duo hex 50 misc In mathematics The sum of Euler s totient function x over the first sixteen integers is 80. Adding up some subsets of its divisors e.g., 1 number 1 , 4 number 4 , 5 number 5 , 10 number 10 , 20 number 20 and 40 number 40 gives 80, hence 80 is a semiperfectnumber . 80 is a m nage number , and is a Harshad numbernumber in base 10 . The Pareto principle also known as the 80 20 rule, states that, for many events, roughly 80 of the effects come from 20 of the causes. ref name NYT citation title Joseph Juran, 103, Pioneer in Quality Control, Dies journal New York Times date March 3, 2008 url http www.nytimes.com 2008 03 03 business 03juran.html last Bunkley first Nick . ref ref name 8020pre citation title What is 80 20 Rule, Pareto s Law, Pareto Principle url http ... element Element 80 Mercury Hg The atomic number of mercury element mercury A rectifier vacuum tube ... wore the number 80 for the majority of his NFL career. The number 80 is also the retired number of Seattle ... permission to unretire his number so Rice could wear it. In other fields Eighty is also the length of the Eighty Years War or Dutch revolt 1568 1648 the standard TCP IP TCP and UDP port port number ..., derived from the number of columns in Punched card IBM 80 column punched card format IBM cards ... 80 Paul Norris is a captain of the North Attleboro Red Rocketeer Football Team in 2011. He wore the number 80. References references External links Commons cat 80 number wiktionary eighty for 80 in other languages. DEFAULTSORT 80 Number Category Integers ab ar 80 az 80 d d bo ... pt Oitenta ru 80 nso 80 nomoro scn Ottanta simple 80 number sl 80 tevilo srn Numro 80 sv ... more details
examplefarm date March 2010 Numbernumber 54 range 50s cardinal fifty four ordinal th ordinal text fifty fourth numeral factorization math 2 cdot 3 3 math prime divisor 1, 2, 3, 6, 9, 18, 27, 54 unicode greek prefix latin prefix misc div wiktionary fifty four 54 fifty four is the natural number following 53 number 53 and preceding 55 number 55 . In mathematics 54 is a 19 polygonal number gonal number . Twice the third power of three, 54 is a Leyland number . 54 can be written as the sum of three Square number square s in three different ways math 7 2 2 2 1 2 6 2 2 3 2 2 5 2 2 2 54 math . It is the smallest number with this property. Like all other multiples of 6, it is a semiperfectnumber . The factorial ... number . The Holt graph has 54 edges. In science The atomic number of xenon is 54. Astronomy Messier ... galaxy in the constellation Cetus The number of years in three Saros cycle s of Eclipse cycle eclipses ... . The Saros number Saros http sunearth.gsfc.nasa.gov eclipse SEsaros SEsaros1 175.html number ... eclipse LEsaros LEsaros1 175.html number of the lunar eclipse series which began on 965 ... s history. For years car number 54 was NASCAR driver Lennie Pond . A score of 54 in golf is colloquially referred to as a perfect round . This score has never been achieved in competition. The number ... Japanese symbols of the 54 chapters of the Tale of Genji In other fields 54 is also The number ... A terrestrial television broadcast television channel number 54 film 54 , a 1998 in film 1998 film ... of authors In the title of a 1960s television show Car 54, Where Are You? The number of the French ... 54th Street The number of cards in a deck of playing card s, if two joker playing card joker s are included The number of countries in Africa Year identifier used on motor vehicles registered in the UK ... 54 A.D. , 54 BC 54 B.C. , 1954, 2054, etc. DEFAULTSORT 54 Number Category Integers ab ... ru 54 nso 54 nomoro simple 54 number sl 54 tevilo srn Numro 54 fi 54 luku sv 54 tal th 54 ... more details
numbers ref An abundant number which is not a semiperfectnumber is called a weird number an abundant number with abundance 1 is called a quasiperfect number , however, none have yet been found. Related ...In number theory , an abundant number or excessive number is a number n for which the sum of divisors &sigma n 2 n , or, equivalently, the sum of proper divisors or aliquot sum s n n . The value &sigma n 2n or s n n is known as the abundance . Examples The first few abundant numbers are 12, 18, 20, 24, 30, 36, 40, 42, 48, 54, 56, 60, 66, 70, 72, 78, 80, 84, 88, 90, 96, 100, 102, OEIS id A005101 . For example, the divisors of 24 are 1, 2, 3, 4, 6, 8, 12 and 24, whose sum is 60. Because 60 is more than 2 24, the number 24 is abundant. Its abundance is 60 2 24 12. Properties The smallest odd abundant number is 945 The smallest not divisible by 2 ... Iannucci Iannucci in 2005 shows how to find the smallest abundant number not divisible by the first k primes. ref citation author D. Iannucci title On the smallest abundant number not divisible ... 1113318127 ref If math A k math represents the smallest abundant number not divisible by the first ... euclid.em 1048515661 ref Every proper multiple of a perfect number , and every multiple of an abundant number, is abundant. Every integer greater than 20161 can be written as the sum of two abundant ... proper factors equals the number itself such as 6 and 28 or more formally, n 2 n , and deficient number s, or numbers the sum of whose proper factors is less than the number itself or n 2 n . The natural number s were first classified as either deficient, perfect or abundant ... glossary page.php?sort AbundantNumber The Prime Glossary Abundant number MathWorld urlname AbundantNumber title Abundant Number PlanetMath urlname AbundantNumber title abundant number id 7869 References ... no Overskuddstall pt N mero abundante ru simple Abundant number sk Abundantn slo ... more details
84 eighty four is the natural number following 83 number 83 and preceding 85 number 85 . Numbernumber 84 range 80s cardinal eighty four ordinal th ordinal text eighty fourth numeral 84 factorization math 2 2 cdot 3 cdot 7 math prime divisor 1, 2, 3, 4, 6, 7, 12, 14, 21, 28, 42, 84 roman LXXXIV unicode greek prefix latin prefix bin 1010100 oct duo hex 54 misc In mathematics File Hepteract ortho petrie.svg thumb 200px left A hepteract is a seven dimension al hypercube with 84 penteract 5 faces Eighty four is the sum of the first seven triangular number s making it a tetrahedral number , as well as the sum of a twin prime 41 43 . Being thrice a perfect number, 84 is itself a semiperfectnumber . Eighty four is also the lim sup of the largest finite subgroup of the mapping class group of a genus math g math surface divided by math g math . A hepteract is a seven dimension al hypercube with 84 penteract 5 faces In astronomy Messier object Messier 84 M84 , a visual magnitude magnitude 11.0 lenticular galaxy in the constellation Virgo constellation Virgo The New General Catalogue http www.ngcic.org object NGC 84 , a single star in the constellation Andromeda constellation Andromeda The Saros cycle Saros number of the solar eclipse series which began on 181 April 14 and ended on 1099 May 22. The duration of Saros series 84 was 1280.1 years, and it contained 72 solar eclipses. ref http eclipse.gsfc.nasa.gov SEsaros SEsaros084.html ref Further, the number of the lunar eclipse series which began on 96 September 13 and ended on 1401 February 28. The duration of Saros series 84 was 1496.5 years, and it contained 84 lunar eclipses. ref http eclipse.gsfc.nasa.gov LEsaros LEsaros084.html ... dial dial 84 for Vietnam Eighty four is also The year AD 84 , 84 BC , or 1984. The atomic number of polonium The model number of Harpoon missile WGS 84 The latest revision of the World Geodetic System , a fixed global reference frame for the Earth. The house number of 84 Avenue Foch The number of the French ... more details
latin prefix misc 56 fifty six is the natural number following 55 number 55 and preceding 57 number 57 . Mathematics 56 is the sum of the first six triangular number s making it a tetrahedral number , as well as the sum of six consecutive prime number primes 3 5 7 11 13 17 . It is also a tetranacci number and a pronic number . Adding up the divisors of 1 through 8 gives 56. Since 56 is twice a perfect number , it is itself a semiperfectnumber . Since it is possible to find sequences of 56 consecutive ...examplefarm date March 2010 Numbernumber 56 range 50s cardinal fifty six ordinal th ordinal text numeral ..., 56 is an Erd s Woods number . The Hadamard s maximal determinant problem maximum determinant in an 8 ..., technology, and biology The atomic number of barium . In humans, olfactory receptor s are categorized ... does not appear to be a real object. The Saros number Saros http sunearth.gsfc.nasa.gov eclipse SEsaros SEsaroscat.html number of the solar eclipse series which began on 1172 July 17 and ended on 144 ... http sunearth.gsfc.nasa.gov eclipse LEsaros LEsaroscat.html number of the lunar eclipse series ... 72 lunar eclipses. Music Number of times the word Yeah is used by Michael Stipe from the band R.E.M. in the song Man on the Moon song Man on the Moon . The number of times the word Yeah ... song. Television and film The car number of Ray Peyton, Jr. Breckin Meyer in Herbie Fully Loaded . Gamal Abdel Nasser Nasser 56 documentary. Sports In baseball , the number of consecutive games in which ... ian politician, En as Carneiro has an odd way of repeating the number of his party, Fifty Six cinq enta ... thus made sure of the exact number. Isoroku Yamamoto , named Isoroku because his father s age was 56 ... in the list of ethnic groups in China . Geography The name of the town Fifty Six, Arkansas . The number ... and 90044 are others . 56 is the number of the French department Morbihan . Archaeology The number ... publisher National Geographic date June 2008 ref Cosmogony According to Aristotle , 56 is the number ... more details
examplefarm date March 2010 Numbernumber 48 range 40s cardinal forty eight ordinal th ordinal text forty ... number following 47 number 47 and preceding 49 number 49 . It is one third of a gross unit gross or four dozen s. In mathematics Forty eight is a double factorial of 6 number 6 , a highly composite number . Like all other multiples of 6, it is a semiperfectnumber . 48 is the second 17 polygonal number gonal number . 48 is in abundant number abundance having an aliquot sum of 76. It is the lowest composite number to fall into the 41 aliquot tree having the 7 aliquot number sequence, 48 ... number with exactly ten divisors. There are 11 solutions to the equation Euler s totient ... any integer below 48, making 48 a highly totient number . Since the greatest prime factor of 48 sup 2 sup 1 2305 is 461, which is clearly more than 48 twice, 48 is a St rmer number. 48 is in base 10 a Harshad number . It has 24, 2, 12,and 4 as factors. In science The atomic number of cadmium The number ... constellation Andromeda The Saros number Saros http sunearth.gsfc.nasa.gov eclipse SEsaros SEsaroscat.html number of the solar eclipse series which began on 1331 February 8 and ended on 15 April ... http sunearth.gsfc.nasa.gov eclipse LEsaros LEsaroscat.html number of the lunar eclipse series which ... and Universe. Buddhism was the result. In music 48 is twice the total number of major and minor .... In sports 48 is the number of a NASCAR car owned by Hendrick Motorsports . It is currently being driven by 5 time and defending NASCAR Sprint Cup champion Jimmie Johnson . 48 is the retired number ... eight may also refer to the code for international direct dial phone calls to Poland the model number ... is a book by Robert Greene popular psychologist Robert Greene The number 48 in ASCII is what you add to any single digit integer to convert to its ASCII value MAC address uses 48 bit 6 byte The number ... tall nn Talet 48 pnb 48 pl 48 liczba pt Quarenta e oito ru 48 nso 48 nomoro simple 48 number ... more details
examplefarm date March 2010 Numbernumber 66 range 60s cardinal sixty six ordinal th ordinal text numeral factorization math 2 cdot 3 cdot 11 math prime divisor 1, 2, 3, 6, 11, 22, 33, 66 unicode greek prefix latin prefix misc 66 sixty six is the natural number following 65 number 65 and preceding 67 number 67 . Usages of this number include Mathematics 66 is a sphenic number , a triangular number , a hexagonal number , and a semi meandric number . Being a multiple of a perfect number , 66 is itself a semiperfectnumber . Since it is possible to find sequences of 66 consecutive integers such that each inner member shares a factor with either the first or the last member, 66 is an Erd s Woods number . Science The atomic number of dysprosium , a lanthanide Astronomy Messier object Spiral Galaxy ... in the constellation Cetus The Saros number Saros http sunearth.gsfc.nasa.gov eclipse SEsaros SEsaros1 175.html number of the solar eclipse series which began on 12 March 756 and ended on 1 May 542 ... sunearth.gsfc.nasa.gov eclipse LEsaros LEsaros1 175.html number of the lunar eclipse series which ..., and it contained 84 lunar eclipses. Sports The National Football League retired jersey number 66 for Green Bay Packers linebacker Ray Nitschke . The last Packer to wear number 66 before it was retired ... as Lex Luger . Jersey number 66 was retired by the Pittsburgh Penguins National Hockey League in honor ... States The calling codes international direct dialing IDD code for Thailand The number of the French ... six game The total number of books in the Protestant edition of the Bible Old Testament and New Testament combined The total number of chapters in the Bible book of Isaiah The number of verses in Chapter ... lines 66 is the number of hot dogs eaten by World record holder Joey Chestnut in 15 minutes at the Nathan ... Alchemist , elusive villain Barry the Chopper is imprisoned in cell number 66, which later becomes ... pl 66 liczba pt Sessenta e seis ru 66 nso 66 nomoro simple 66 number sl 66 tevilo srn Numro 66 ... more details
60 sixty Audio en us sixty.ogg Listen is the natural number following 59 number 59 and preceding 61 number 61 . Being three times twenty, 60 is called three 20 number score in some older literature. Numbernumber 60 range 60s cardinal sixty ordinal th ordinal text sixtieth numeral sexagesimal factorization ... prefix latin prefix misc In mathematics Sixty is a composite number with divisors 1 number 1 , 2 number 2 , 3 number 3 , 4 number 4 , 5 number 5 , 6 number 6 , 10 number 10 , 12 number 12 , 15 number 15 , 20 number 20 , 30 number 30 , and 60, making it also a highly composite number . Because 60 is the sum of its unitary divisors excluding itself , it is a unitary perfect number , and it is also an excessive number with an abundance of 48 number 48 . Being ten times a perfect number, 60 is a semiperfectnumber . Sixty is the smallest number divisible by the numbers 1 to 6. There is no smaller number divisible by the numbers 1 to 5 . 60 is the smallest number with exactly 12 divisors. Sixty is the sum of a pair of twin prime s 29 31 , as well as the sum of four consecutive prime number prime s 11 13 17 19 . It is adjacent to two prime numbers 59,61 . It is also the smallest number which ... es made from 6 squares. In geometry , 60 is the number of arcsecond second s in a arcminute minute , and the number of minutes in a degree angle degree . In normal space, the 3 interior angles ... 60 is divisible by the sum of its digits in base 10, it is a Harshad number . A number system with base .... The atomic number of Neodymium is 60, and Cobalt 60 sup 60 sup Co is a radioactive isotopes of cobalt ... Hz . An exbibyte sometimes called exabyte is 2 sup 60 sup byte s. Cultural number systems File Babylonian numerals.svg thumb left 160px The Babylonians used base 60. The Babylonian number system ... motivated by the large number of divisors which 60 has. The sexagesimal measurement of time and of geometric angles is a legacy of the Babylonian system. The number system in the Mali Empire was also ... more details
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