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 A277470 #10 Nov 08 2017 02:31:57
%S A277470 0,1,2,11,104,1249,18264,318163,6425152,147344769,3781848480,
%T A277470 107408279483,3343875651456,113227469886881,4142804357946240,
%U A277470 162871544915116035,6847004160475236352,306495323034774157569,14554502490109085839872,730777840212988501198059
%N A277470 E.g.f.: arcsinh(x)/(1+LambertW(-x)).
%H A277470 G. C. Greubel, <a href="/A277470/b277470.txt">Table of n, a(n) for n = 0..385</a>
%F A277470 a(n) ~ arcsinh(exp(-1)) * n^n.
%F A277470 a(n) ~ (-1 + log(1 + sqrt(1+exp(2)))) * n^n.
%t A277470 CoefficientList[Series[ArcSinh[x]/(1+LambertW[-x]), {x, 0, 25}], x] * Range[0, 25]!
%t A277470 Flatten[{0, Table[Sin[Pi*n/2] * (n-2)!!^2 + Sum[Sin[Pi*k/2] * Binomial[n, k] * (k-2)!!^2 * (n-k)^(n-k), {k, 1, n-1}], {n, 1, 25}]}] (* _Vaclav Kotesovec_, Oct 28 2016 *)
%o A277470 (PARI) x='x+O('x^50); concat([0], Vec(serlaplace(asinh(x)/(1 + lambertw(-x)) ))) \\ _G. C. Greubel_, Nov 07 2017
%Y A277470 Cf. A000312, A086331, A277469.
%K A277470 nonn
%O A277470 0,3
%A A277470 _Vaclav Kotesovec_, Oct 16 2016