Number of iterations of f(x) = sigma(x)-1 on n required to reach a prime.
0, 0, 2, 0, 1, 0, 2, 5, 1, 0, 4, 0, 1, 1, 2, 0, 2, 0, 1, 1, 2, 0, 1, 2, 1, 3, 2, 0, 1, 0, 5, 1, 1, 1
2 seqfan posts
Fri May 7 12:20:30 CEST 2010 [seqfan] Re: Iterating sigma - 1