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 A088561 #10 Aug 06 2021 11:13:01 %S A088561 11,13,18,20,26,36,43,47,53,58,64,79,82,94,98,100,105,116,121,125,126, %T A088561 133,135,142,156,164,167,178,190,193,197,210,216,218,233,248,271,279, %U A088561 286,291,297,305,318,326,331,335,344,347,362,369,374,381,395,400,406 %N A088561 A088555 indexed by A000040. %C A088561 Subset of A049511. %F A088561 a(n) = k such that A000040(k) = A088555(n). %F A088561 a(n) = A000720(A088555(n)). - _Michel Marcus_, Aug 06 2021 %Y A088561 Cf. A023219, A049511, A088555, A090161. %K A088561 nonn,easy %O A088561 1,1 %A A088561 _Ray Chandler_, Nov 28 2003 %E A088561 Offset changed to 1 by _Jinyuan Wang_, Aug 06 2021