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 A301511 #5 Feb 16 2025 08:33:53
%S A301511 1,1,4,14,68,362,2224,14940,110348,878600,7518002,68529122,662709832,
%T A301511 6764329158,72622813172,817239648500,9612724174088,117878757097178,
%U A301511 1503660164683864,19911519090176808,273221610513382028,3878513600608651636,56873187579428449852,860296560100458300892
%N A301511 Expansion of e.g.f. exp(Sum_{k>=1} psi(k)*x^k/k!), where psi() is the Dedekind psi function (A001615).
%C A301511 Exponential transform of A001615.
%H A301511 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/DedekindFunction.html">Dedekind Function</a>
%H A301511 N. J. A. Sloane, <a href="/transforms.txt">Transforms</a>
%F A301511 E.g.f.: exp(Sum_{k>=1} A001615(k)*x^k/k!).
%e A301511 E.g.f.: A(x) = 1 + x/1! + 4*x^2/2! + 14*x^3/3! + 68*x^4/4! + 362*x^5/5! + 2224*x^6/6! + 14940*x^7/7! + ...
%t A301511 psi[n_] := n Sum[MoebiusMu[d]^2/d, {d, Divisors@n}]; a[n_] := a[n] = SeriesCoefficient[Exp[Sum[psi[k] x^k/k!, {k, 1, n}]], {x, 0, n}]; Table[a[n] n!, {n, 0, 23}]
%t A301511 psi[n_] := n Sum[MoebiusMu[d]^2/d, {d, Divisors@n}]; a[n_] := a[n] = Sum[psi[k] Binomial[n - 1, k - 1] a[n - k], {k, 1, n}]; a[0] = 1; Table[a[n], {n, 0, 23}]
%Y A301511 Cf. A001615, A063659, A156303, A300011.
%K A301511 nonn
%O A301511 0,3
%A A301511 _Ilya Gutkovskiy_, Mar 22 2018