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 A330516 #5 Dec 17 2019 08:41:23
%S A330516 1,1,17,601,44225,4589041,781157585,162882093193,48519650017025,
%T A330516 17223202538504161,7898449818361655825,4193448664548573675961,
%U A330516 2779065418077990268214465,2061320859693223620523895761,1836094285018667246330440863185
%N A330516 Expansion of e.g.f. Product_{k>=1} sec(x^k) (even powers only).
%t A330516 nmax = 14; Table[(CoefficientList[Series[Product[Sec[x^k], {k, 1, nmax}], {x, 0, 2 nmax}], x] Range[0, 2 nmax]!)[[n]], {n, 1, 2 nmax + 1, 2}]
%Y A330516 Cf. A000364, A203716, A229263, A270294, A270662, A270663, A270664, A270665, A270666, A330514, A330515, A330517.
%K A330516 nonn
%O A330516 0,3
%A A330516 _Ilya Gutkovskiy_, Dec 17 2019