摘要：N^N = 10^（N*log10(N))N*log10(N) = inpart(整数部分)+fracpart（分数部分）-》N^N = 10^inpart*10^fracpat.10^inpart不影响最高位的数，所以最高位的数就是10^fracpart最高位的数。参考资料：http://www.cnblogs.com/jieao111/archive/2009/08/02/1536997.ht... 阅读全文

摘要：Def: Phi(n) = # of factors a s.t. (a, n) = 1Thm: Let p1, p2... pk be all prime factors of n,then,Phi(n) = n(1 - 1/p1)(1 - 1/p2)... (1 - 1/pk).Proof 1:It suffices to show that1) Phi(p) = p2) Phi(p^k) =... 阅读全文