OFFSET
1,2
FORMULA
If p is prime, a(p) = 1 + p.
E.g.f.: Sum_{k>0} x^k/k! * exp(x^k/k!).
PROG
(PARI) a(n) = n!*sumdiv(n, d, 1/((d-1)!*(n/d)!^d));
(PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(sum(k=1, N, x^k/k!*exp(x^k/k!))))
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Feb 23 2024
STATUS
approved