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 A362860 #13 Feb 16 2025 08:34:05
%S A362860 1,2,31,629,18025,662639,29752957,1578248867,96577834801,
%T A362860 6696994946543,518978239136341,44448540938239811,4169223860364566857,
%U A362860 425060509005908328071,46801425208023247277965,5534686715620432932442619,699654866766940182167273185
%N A362860 Expansion of e.g.f. exp(-x) / (1 + LambertW(-3*x)).
%H A362860 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/LambertW-Function.html">Lambert W-Function</a>.
%F A362860 G.f.: Sum_{k>=0} (3*k*x)^k / (1 + x)^(k+1).
%F A362860 a(n) = (-1)^n * Sum_{k=0..n} (-3*k)^k * binomial(n,k).
%o A362860 (PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(exp(-x)/(1 + lambertw(-3*x))))
%Y A362860 Column k=3 of A362019.
%Y A362860 Cf. A091482, A362858.
%K A362860 nonn,easy
%O A362860 0,2
%A A362860 _Seiichi Manyama_, May 05 2023