OFFSET
0,3
FORMULA
a(n) ~ 2^((n-1)/2) * exp(Pi*n/4 - n) * n^n. - Vaclav Kotesovec, Oct 02 2017
a(0) = a(1) = 1; a(n) = 2 * Sum_{k=1..n-1} binomial(n,k) * a(k) * a(n-k-1). - Ilya Gutkovskiy, Nov 21 2020
MATHEMATICA
Table[n! SeriesCoefficient[Exp[n ArcSin[x]], {x, 0, n}], {n, 0, 19}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Oct 02 2017
STATUS
approved