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 A323721 #9 Jan 29 2019 05:01:15
%S A323721 0,1,2,-3,-6,50,-13,-1498,6234,59145,-748678,-1415238,92962179,
%T A323721 -411570250,-11993577118,167710062977,1224967301754,-51920085859710,
%U A323721 135335259830867,14992073315394822,-201575378391009366,-3667884891055854535,128570113943360964602,209758874692705861322
%N A323721 Expansion of e.g.f. log(2*exp(x/2)*cosh(sqrt(5)*x/2) - 1).
%F A323721 E.g.f.: log(1 + Sum_{k>=1} Lucas(k)*x^k/k!).
%F A323721 a(0) = 0; a(n) = Lucas(n) - (1/n)*Sum_{k=1..n-1} binomial(n,k)*Lucas(n-k)*k*a(k).
%p A323721 seq(n!*coeff(series(log(2*exp(x/2)*cosh(sqrt(5)*x/2)-1),x=0,24),x,n),n=0..23); # _Paolo P. Lava_, Jan 28 2019
%t A323721 nmax = 23; CoefficientList[Series[Log[2 Exp[x/2] Cosh[Sqrt[5] x/2] - 1], {x, 0, nmax}], x] Range[0, nmax]!
%t A323721 a[n_] := a[n] = LucasL[n] - Sum[Binomial[n, k] LucasL[n - k] k a[k], {k, 1, n - 1}]/n; a[0] = 0; Table[a[n], {n, 0, 23}]
%Y A323721 Cf. A000032, A000204, A007553, A112005, A294222.
%K A323721 sign
%O A323721 0,3
%A A323721 _Ilya Gutkovskiy_, Jan 25 2019