OFFSET
0,3
MATHEMATICA
a[0] = 1; a[n_] := a[n] = Sum[Binomial[n - 1, k]^3 a[k] a[n - k - 1], {k, 0, n - 1}]; Table[a[n], {n, 0, 17}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Jul 09 2021
STATUS
approved