nPostednon July 17, 2014
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nInlove a math holiday, like Pi Day (3/14, because pi =n3.14…) or Mole Day (6:02 on 10/23, because Avogadro’s Number isn6.02 * 10^23).
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nTodaynis a math holiday! It celebrates the number 17, which is the seventhnprime number (hence 7/17). But what is the connection to yellow pigs,nyou may ask?
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nInnthe early 1960s, when holiday creators Michael Spivak and David C.nKelly were students at Princeton University, majoring in math, theynbegan to list interesting properties of the number 17. Somehow, anyellow pig with 17 eyelashes was born – and it’s been a thing evernsince.
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nOkay,nthat still sounds pretty random, doesn’t it? But how does anyntradition start? How did the birth of a religious figure getnassociated with a gentleman who lives at the North Pole? How did anfeast for Saint Patrick get associated with painting faces green andnpouring green coloring into rivers—even though St. Patrick’s flagnis red and white? n
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nAtnany rate, for probably completely random reasons (or no reason),nSpivak and Kelly invented a yellow pig. Since then, Spivak hasnwritten many famous math textbooks – and he has included yellownpigs in them. Kelly runs a summer program for high school studentsnwho are “into” math, and he has introduced them to the “cult”nof the Yellow Pig. Kelly has a collection of hundreds of yellow pigs, and a fewnother mathematicians have been inspired to collect them, too.
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nFornmore than three decades, mathematicians and math students havencelebrated Yellow Pig Day by wearing shirts decorated with yellownpigs, playing a frisbee game called Ultimate, displaying collectionsnof yellow pigs and origami yellow pigs, singing Yellow Pig Day carolsn(I kid you not), and eating a yellow pig cake. Some people exchangenyellow pigs and mathematical knick knacks and other gifts.
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nOfncourse, the very best way to celebrate Yellow Pig Day is to learnnmore about the number 17!
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n17nis not only a prime number (which means that no two numbersnmultiplied together equal 17 – other than 1 and 17 itself), but itnis the sum of the first four prime numbers:
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n 2n+ 3 + 5 + 7 = 17
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n17nis the only known prime that is equal to the sum of the digits of itsncube:
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n 17n* 17 * 17 = 4913 n
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n 4n+ 9 + 1 + 3 = 17
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n17nis the only prime that is the average of two consecutive Fibonaccinnumbers:
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n Fibonaccinnumbers are the sum of each two previous numbers:
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n 1,n1 – 1 + 1 = 2
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n 1,n1, 2, 3 – 2 + 3 = 5
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n 1,n1, 2, 3, 5 – 3 + 5 = 8
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n andnso on…
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n 1,n1, 2, 3, 5, 8, 13, 21, 34, 55, 89…
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n 13n+ 21 = 34
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n 34ndivided by 2 = 17
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nAlsonon this date:
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nWrong-WaynCorrigan Day
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nAnniversarynof an ancient solar eclipse
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nDisneyland’snbirthday
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nPlannahead:
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nChecknout my Pinterest boards for:
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nJulyn holidays
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nJulyn birthdays
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nHistoricaln anniversaries in July
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nAndnhere are my Pinterest boards for:
nnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn
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nAugustn holidays
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nAugustn birthdays
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nHistoricaln anniversaries in August
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