A290376 Prime Fubini numbers.

3, 13, 541, 47293, 7087261, 526858348381

Offset: 1

Author

Amiram Eldar, Jul 28 2017

Keywords

• nonn
• more

Comments

Corresponding indices are 2, 3, 5, 7, 9, 13, ... with no more up to 12000.

Crossrefs

Cf. A000670.

Programs

Mathematica

a[0] = 1; a[n_] := a[n] = Sum[Binomial[n, k]*a[n - k], {k, 1, n}]; Select[a@# & /@ Range@ 20, PrimeQ@# &]

PARI

lista(nn) = for (n=1, nn, if (isprime(fn=sum(k=1, n, k!*stirling(n, k, 2))), print1(fn, ", "));); \\ Michel Marcus, Aug 02 2017