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 A330518 #4 Dec 17 2019 08:41:44
%S A330518 1,1,3,14,77,536,4471,41474,437737,5206120,67098091,944705662,
%T A330518 14495605277,237203399044,4162492013135,78089687760842,
%U A330518 1545654292223825,32385137447167280,716473190874986323,16611710217097325366,404119023609893926405
%N A330518 Expansion of e.g.f. Product_{k>=1} (sec(x^k) + tan(x^k)).
%t A330518 nmax = 20; CoefficientList[Series[Product[(Sec[x^k] + Tan[x^k]), {k, 1, nmax}], {x, 0, nmax}], x] Range[0, nmax]!
%Y A330518 Cf. A000111, A203716, A229263, A270294, A270662, A270663, A270664, A270665, A270666, A330514, A330515, A330516, A330517.
%K A330518 nonn
%O A330518 0,3
%A A330518 _Ilya Gutkovskiy_, Dec 17 2019