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 A173001 #3 Mar 30 2012 18:52:39 %S A173001 1,3,4,5,7,8,11,12,13,15,16,17,19,20,21,22,24,25,32,35,42,43,44,48,49, %T A173001 50,52,55,56,60,61,63,69,70,71,73,74,79,81,82,84,85,86,87,88,92,93,94, %U A173001 98,101,106,107,108,109,110,112,115,117,120,123,126,127,131,132,135,137 %N A173001 Values of n such that exactly one of 5n+1 and 5n^2+5n+1 is prime. %Y A173001 Cf. A090563. %K A173001 nonn %O A173001 1,2 %A A173001 _Juri-Stepan Gerasimov_, Feb 07 2010 %E A173001 56 inserted by _R. J. Mathar_, Mar 09 2010