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 A320258 #5 Oct 08 2018 18:15:51
%S A320258 1,1,-3,10,81,-4724,156205,-4406814,76958273,3775676248,-698309272899,
%T A320258 72802616429830,-6310377003297455,435451735391849892,
%U A320258 -10028808876450831571,-4757293711381352201774,1464955115044140633346305,-310063138309576689774123728,55179706013436631385620675837
%N A320258 a(n) = n! * [x^n] exp(x*exp(-n*x)).
%F A320258 a(n) = [x^n] Sum_{k>=0} x^k/(1 + n*k*x)^(k+1).
%F A320258 a(n) = Sum_{k=0..n} binomial(n,k)*(-n*k)^(n-k).
%t A320258 Table[n! SeriesCoefficient[Exp[x Exp[-n x]], {x, 0, n}], {n, 0, 18}]
%t A320258 Table[SeriesCoefficient[Sum[x^k/(1 + n k x)^(k + 1), {k, 0, n}], {x, 0, n}], {n, 0, 18}]
%t A320258 Join[{1}, Table[Sum[Binomial[n, k] (-n k)^(n - k), {k, 0, n}], {n, 18}]]
%Y A320258 Cf. A003725, A295552.
%K A320258 sign
%O A320258 0,3
%A A320258 _Ilya Gutkovskiy_, Oct 08 2018