Numbers n such that the sum of divisors of n is a pentagonal number.
1, 6, 11, 104, 116, 129, 218, 363, 408, 440, 481, 534, 566, 568, 590, 638, 646, 684
2 seqfan posts
Sun Sep 26 06:48:14 CEST 2010 [seqfan] Re: n-th number whose sum of divisors is a n-gonal number