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 A379933 #21 Jan 08 2025 02:42:58
%S A379933 1,4,22,158,1408,15002,186100,2634998,41937136,741170834,14402727484,
%T A379933 305225470046,7005711916840,173134991854970,4583675648417044,
%U A379933 129424786945875398,3882446011526729440,123304773913531035170,4133369745467043807340,145840627118145774415214
%N A379933 Expansion of e.g.f. 1/( exp(-x) - x )^2.
%H A379933 Seiichi Manyama, <a href="/A379933/b379933.txt">Table of n, a(n) for n = 0..410</a>
%F A379933 E.g.f.: B(x)^2, where B(x) is the e.g.f. of A072597.
%F A379933 a(n) = n! * Sum_{k=0..n} (k+1) * (k+2)^(n-k)/(n-k)!.
%o A379933 (PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(1/(exp(-x)-x)^2))
%o A379933 (PARI) a(n) = n!*sum(k=0, n, (k+1)*(k+2)^(n-k)/(n-k)!);
%Y A379933 Cf. A072597, A379942, A379943.
%Y A379933 Cf. A379934, A379936.
%Y A379933 Cf. A358738, A377529.
%K A379933 nonn
%O A379933 0,2
%A A379933 _Seiichi Manyama_, Jan 06 2025