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%I #5 Sep 20 2024 15:37:18
%S 0,1,2,15,112,1285,17616,299299,5946368,136497897,3544641280,
%T 102858065431,3297199331328,115730076038317,4414151526557696,
%U 181797547951527915,8040649885153755136,380100842138029431121,19125314442962053300224,1020539634854353310016415,57563650890815727219507200
%N Expansion of e.g.f. -LambertW(-x/(1-x^2)).
%F a(n) ~ (1 + 4*exp(-2))^(1/4) * 2^n * n^(n-1) / (exp(n) * (sqrt(4 + exp(2)) - exp(1))^n).
%t nmax=25; CoefficientList[Series[-LambertW[-x/(1-x^2)], {x, 0, nmax}], x] * Range[0, nmax]!
%Y Cf. A052871, A376106.
%K nonn
%O 0,3
%A _Vaclav Kotesovec_, Sep 20 2024