A385990 a(0) = 1; a(n) = Sum_{k=0..n-1} (2^k + 3^k) * binomial(n-1,k) * a(k) * a(n-1-k).
1, 2, 14, 250, 10762, 1160726, 334178342, 269864173450, 629119441422346, 4300094237465965718, 86926579696107616781126, 5223854240144609158089474250, 936213967612878042630582862931818, 501401563584674616157299481286097996374, 803517566423095869415868021817376896171061478
Offset: 0
Keywords
Crossrefs
Cf. A385620.
Programs
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PARI
a_vector(n) = my(v=vector(n+1)); v[1]=1; for(i=1, n, v[i+1]=sum(j=0, i-1, (2^j+3^j)*binomial(i-1, j)*v[j+1]*v[i-j])); v;
Formula
E.g.f. A(x) satisfies A'(x) = A(x) * (A(2*x) + A(3*x)).