OFFSET
0,2
LINKS
Vaclav Kotesovec, Table of n, a(n) for n = 0..350
FORMULA
G.f. satisfies: A(x) = (1 + x*d/dx[x*A(x)] )^3.
a(n) ~ c * 3^n * n! * n^(2/3), where c = 0.7528584991179137287053869... - Vaclav Kotesovec, Oct 23 2020
PROG
(PARI) {a(n)=local(A=1+x*O(x^n)); for(i=1, n, A=(1+x*deriv(x*A))^3); polcoeff(A, n, x)}
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Nov 04 2005
STATUS
approved