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%I #14 Oct 27 2024 09:03:41
%S 1,0,6,9,516,3075,149418,1956171,95139432,2099836899,108189172830,
%T 3465051871083,194015893087404,8207832658120563,505114926236953074,
%U 26525536061251639275,1800555184934893332048,112493970299385975997635,8415880480577316204054630
%N Expansion of e.g.f. (1/x) * Series_Reversion( x/(1 + x*(exp(x) - 1))^3 ).
%H <a href="/index/Res#revert">Index entries for reversions of series</a>
%F E.g.f. satisfies A(x) = ( 1 + x*A(x) * (exp(x*A(x)) - 1) )^3.
%F E.g.f.: B(x)^3, where B(x) is the e.g.f. of A371272.
%F a(n) = 3 * n! * (3*n+2)! * Sum_{k=0..floor(n/2)} Stirling2(n-k,k)/( (n-k)! * (3*n-k+3)! ).
%o (PARI) a(n) = 3*n!*(3*n+2)!*sum(k=0, n\2, stirling(n-k, k, 2)/((n-k)!*(3*n-k+3)!));
%Y Cf. A371119, A377392.
%Y Cf. A371272.
%K nonn
%O 0,3
%A _Seiichi Manyama_, Oct 27 2024