This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A225675 #4 May 13 2013 01:28:45 %S A225675 2,7,9,16,17,18,25,26,31,53,81,97,121,127,162,241,250,256,337,361,486, %T A225675 577,625,841,1249,1458,2186,2401,2662,3361,3481,3697,3721,4373,4801, %U A225675 5041,6241,6961,8191,10201,10657,13121,14641,17161,19321,23761,25537,28561,31249,32257 %N A225675 Numbers n such that triangular(n) is representable as p*w, where p is a prime number and w is a prime power (A025475). %C A225675 Corresponding triangular numbers are in A225674. %C A225675 The subsequence of even terms begins: 2, 16, 18, 26, 162, 250, 256, 486, 1458, 2186, 2662, 39366, 48778, 65536, 410758, 715822, 1594322, 2450086, 6615898, 12872686, 13935742, 15290746, 23394166, 38930218, 41022298, 86093442, ... %Y A225675 Cf. A000040, A000217, A025475, A225674. %K A225675 nonn %O A225675 1,1 %A A225675 _Alex Ratushnyak_, May 12 2013