はてなブックマーク - Permutation -- from Wolfram MathWorld https://b.hatena.ne.jp/entry/s/mathworld.wolfram.com/Permutation.html A permutation, also called an "arrangement number" or "order," is a rearrangement of the elements of an ordered list into a one-to-one correspondence with itself. The number of permutations on a se... tuka_koto https://b.hatena.ne.jp/tuka_koto/20120429#bookmark-9980161 2012-04-29T09:35:12Z MathWorld 集合論 yoyama https://b.hatena.ne.jp/yoyama/20120212#bookmark-9980161 2012-02-12T03:47:22Z meganii https://b.hatena.ne.jp/meganii/20091123#bookmark-9980161 2009-11-23T04:24:55Z *プログラミング niseissa https://b.hatena.ne.jp/niseissa/20080911#bookmark-9980161 2008-09-11T09:21:00Z *あとで試す *ネタ *プログラミング