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 A205129 #5 Mar 30 2012 18:58:10 %S A205129 1,2,3,7,1,9,2,29,3,9,5,12,6,2,9,121,10,16,14,12,15,5,20,48,21,54,4, %T A205129 52,28,9,35,497,36,90,24,33,45,14,8,71,55,61,65,7,16,20,77,138,30,82, %U A205129 13,63,91,27,51,71,23,252,119,12 %N A205129 Least k such that n divides a difference between distinct hexagonal numbers, ordered as in A205128. %C A205129 For a guide to related sequences, see A204892. %t A205129 (See the program at A205130.) %Y A205129 Cf. A205130, A204892. %K A205129 nonn %O A205129 1,2 %A A205129 _Clark Kimberling_, Jan 25 2012