220 and 284 (Amicable Numbers) - Numberphile
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Uploaded by numberphile on Dec 19, 2011
Why do 220 and 284 get along so well? Dr James Grime introduces us to the world of so-called amicable numbers.
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Videos by Brady Haran
James has his own website at http://singingbanana.com/
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Is there a triplet of numbers like this? Adding the factors of number x gives number y, the sum of the factors of number y give number z, and the sum of the factors of number z give x again? What about for longer chains?
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@themetalASIAN guess why? forever alone guy.
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Really romantic 3
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only one dislike... wow
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I just came here from the 'Perfect Numbers' video, and these amicable numbers sound pretty similar to the perfect ones! Maybe it would be fun to figure out groups of numbers with a different cycle length (eg. a's divisors added up produce b, b's divisors produce c, and c's divisors produce a) and maybe find some patterns...
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Awww that is so sweet. I want to make a set of those pendants for when I find my 284
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I wish i had massive brown paper frames whenever i had a math problem to solve on the go =P
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@cheetah465 Whoah, Cheeta, if ya eat all those apples, you're gonna get a eicked bad tummy ache.
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Im a troll, I go around liking all the numberphile videos. You mad haters.
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@TheRealDJLO nerds like me, pencils, and A LOOOOOOOOOOOOOOT of time
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FOREVER 220 :(
tekproxy 2 months ago 136
How do you like them apples?
FlamezagKing 1 month ago 58