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 A355376 #14 Jun 30 2022 10:15:42
%S A355376 1,1,1,-5,-29,271,3091,-61025,-744029,34875871,211095331,-37415273345,
%T A355376 300267009571,61080483836191,-2133136977892829,-119576844586022465,
%U A355376 11752559492568148771,94348367247493654111,-68793303669649907424989,2764486881197709482575615
%N A355376 a(n) = Sum_{k=0..n} k! * (-k)^(n-k) * Stirling2(n,k).
%F A355376 E.g.f.: Sum_{k>=0} (1 - exp(-k * x))^k / k^k.
%t A355376 a[n_] := Sum[k! * (-k)^(n - k) * StirlingS2[n, k], {k, 0, n}]; a[0] = 1; Array[a, 20, 0] (* _Amiram Eldar_, Jun 30 2022 *)
%o A355376 (PARI) a(n) = sum(k=0, n, k!*(-k)^(n-k)*stirling(n, k, 2));
%o A355376 (PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(sum(k=0, N, (1-exp(-k*x))^k/k^k)))
%Y A355376 Cf. A229234, A355373, A355375.
%K A355376 sign
%O A355376 0,4
%A A355376 _Seiichi Manyama_, Jun 30 2022