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 A173416 #3 Mar 30 2012 18:52:39 %S A173416 1,2,4,7,8,9,10,11,13,15,17,18,22,25,27,28,30,33,34,38,39,41,43,46,49, %T A173416 50,52,56,59,62,63,64,66,69,72,73,75,76,80,81,85,91,92,93,95,96,98,99, %U A173416 105,108,109,112,113,115,118,123,125,126,127,134,135,137,140,141,143 %N A173416 Exactly one of 2n^2-1 and 2n^2+1 is prime. %C A173416 Numbers in A089001 or in A066049 but not in both. [From _R. J. Mathar_, Mar 09 2010] %e A173416 a(1)=1 because 2*1^2-1=1 is nonprime and 2*1^2+1=3 is prime. %K A173416 nonn %O A173416 1,2 %A A173416 _Juri-Stepan Gerasimov_, Mar 01 2010 %E A173416 37 removed by _R. J. Mathar_, Mar 09 2010