OFFSET
0,3
FORMULA
a(0) = 1; a(n) = (n-1)! * Sum_{p<=n, p prime} p^2 * a(n-p)/(n-p)!.
PROG
(PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(exp(sum(k=1, N, isprime(k)*k*x^k))))
(PARI) a(n) = if(n==0, 1, (n-1)!*sum(k=1, n, isprime(k)*k^2*a(n-k)/(n-k)!));
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Apr 28 2022
STATUS
approved