A385650 E.g.f. A(x) satisfies A(x) = exp( x*(A(x) + A(2*x))^2 ).

1, 4, 112, 8800, 1586944, 624664064, 536747751424, 1018102925488128, 4288756843049058304, 40076190507961751044096, 826422665125748814526283776, 37363126329930414708850363990016, 3679235193626553722088195031035805696, 784317990902751658071943156321585144528896

Offset: 0

Author

Seiichi Manyama, Jul 06 2025

Keywords

• nonn

Crossrefs

Cf. A385619, A385651.

Cf. A168600, A385648.

Formula

a(0) = 1; a(n) = (n-1)! * Sum_{i, j, k>=0 and i+j+k=n-1} (n-i) * (2^j+1) * (2^k+1) * a(i) * a(j) * a(k)/(i! * j! * k!).