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 A036719 #5 Jul 08 2025 21:54:39 %S A036719 1,1,1,3,7,22,65,212,697,2372,8179,28703,101851,365393,1322034, %T A036719 4820378,17691018,65306700,242317423,903242615,3380707920,12700575742, %U A036719 47874113728,181013422393,686341240781,2609093456212,9941953711409 %N A036719 G.f. satisfies A(x) = 1 + x*cycle_index(Cyclic(4), A(x)). %Y A036719 Cf. A036717, A036718. %K A036719 nonn %O A036719 0,4 %A A036719 _N. J. A. Sloane_