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 A330387 #9 Dec 15 2019 02:41:14 %S A330387 1,2,12,62,420,3782,40572,463262,5708820,80773622,1319927532, %T A330387 23675250062,447145154820,8830952572262,185694817024092, %U A330387 4246473212654462,105754322266866420,2811068529133151702,78039884046777282252,2243558766132057764462 %N A330387 Expansion of e.g.f. Sum_{k>=1} (-1)^(k + 1) * (exp(x) - 1)^k / (k * (1 - (exp(x) - 1)^k)). %F A330387 E.g.f.: -Sum_{k>=1} log(1 - (exp(x) - 1)^(2*k - 1)). %F A330387 E.g.f.: A(x) = log(B(x)), where B(x) = e.g.f. of A305550. %F A330387 exp(Sum_{n>=1} a(n) * log(1 + x)^n / n!) = g.f. of A000009. %F A330387 a(n) = Sum_{k=1..n} Stirling2(n,k) * (k - 1)! * A000593(k). %F A330387 E.g.f.: Sum_{k>=1} log(1 + (exp(x) - 1)^k). - _Vaclav Kotesovec_, Dec 15 2019 %F A330387 a(n) ~ n! * Pi^2 / (24 * (log(2))^(n+1)). - _Vaclav Kotesovec_, Dec 15 2019 %t A330387 nmax = 20; CoefficientList[Series[Sum[(-1)^(k + 1) (Exp[x] - 1)^k/(k (1 - (Exp[x] - 1)^k)), {k, 1, nmax}], {x, 0, nmax}], x] Range[0, nmax]! // Rest %t A330387 Table[Sum[StirlingS2[n, k] (k - 1)! Sum[Mod[d, 2] d, {d, Divisors[k]}], {k, 1, n}], {n, 1, 20}] %t A330387 nmax = 20; Rest[CoefficientList[Series[Sum[Log[1 + (Exp[x] - 1)^k], {k, 1, nmax}], {x, 0, nmax}], x] * Range[0, nmax]!] (* _Vaclav Kotesovec_, Dec 15 2019 *) %Y A330387 Cf. A000009, A000593, A000629, A008277, A088311, A265024, A305550, A330353, A330388. %K A330387 nonn %O A330387 1,2 %A A330387 _Ilya Gutkovskiy_, Dec 12 2019