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 A351882 #9 Feb 24 2022 02:22:51
%S A351882 1,1,2,9,42,255,1785,14406,131236,1328037,14809965,180014054,
%T A351882 2371072374,33607312219,510183508471,8255546409722,141855645636152,
%U A351882 2579236008913689,49471832899923129,998261936044450726,21138674688880283370,468687157358947546415,10858634384569444410179
%N A351882 Expansion of e.g.f. 1 / (1 - x)^sec(x).
%F A351882 a(0) = 1; a(n) = Sum_{k=1..n} binomial(n-1,k-1) * |A009429(k)| * a(n-k).
%F A351882 a(n) ~ n! / (Gamma(1/cos(1)) * n^(1 - 1/cos(1))) * (1 + (1 - 1/cos(1)) * sin(1) * log(n) / (n*cos(1)^2)). - _Vaclav Kotesovec_, Feb 24 2022
%t A351882 nmax = 22; CoefficientList[Series[1/(1 - x)^Sec[x], {x, 0, nmax}], x] Range[0, nmax]!
%o A351882 (PARI) my(x='x+O('x^30)); Vec(serlaplace(1/(1-x)^(1/cos(x)))) \\ _Michel Marcus_, Feb 23 2022
%Y A351882 Cf. A009196, A009429, A351880, A351883.
%K A351882 nonn
%O A351882 0,3
%A A351882 _Ilya Gutkovskiy_, Feb 23 2022