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 A246315 #14 Sep 25 2014 14:13:26 %S A246315 1,9,37,157,713,2737,11421,44021,176801,683369,2695829,10433229, %T A246315 40796217 %N A246315 A246314(2^n-1). %e A246315 a(1)=9 and a(2)=37 are illustrated in A246314. %Y A246315 Cf. A246314. %K A246315 nonn,more %O A246315 0,2 %A A246315 _N. J. A. Sloane_, Aug 26 2014 %E A246315 a(9) from _Alois P. Heinz_, Sep 01 2014 %E A246315 a(10)-a(12) from _N. J. A. Sloane_, Sep 04 2014