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 A137242 #4 Mar 30 2012 18:40:03 %S A137242 4,6,8,9,11,12,14,15,16,18,19,21,22,23,24,25,27,29,31,32,36,37,38,39, %T A137242 40,44,48,50,51,54,55,56,58,59,63,65,67,70,71,72,73,74,75,76,77,78,79, %U A137242 84,85,86,87,88,90,92,93,94,95,96,100,102,103,105,107,108,110,111,112,117 %N A137242 Numbers n such that A116127(n) = 2. %C A137242 See also A049579 for a(n) = n iff A116127(n) = 2n with n>0. %Y A137242 Cf. A049579, A116127. %K A137242 easy,nonn %O A137242 1,1 %A A137242 _Giovanni Teofilatto_, Mar 09 2008 %E A137242 Corrected (71 inserted) by _R. J. Mathar_, Apr 22 2010