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%I #10 Aug 03 2017 11:37:57
%S 3,13,541,47293,7087261,526858348381
%N Prime Fubini numbers.
%C Corresponding indices are 2, 3, 5, 7, 9, 13, ... with no more up to 12000.
%t a[0] = 1; a[n_] := a[n] = Sum[Binomial[n, k]*a[n - k], {k, 1, n}]; Select[a@# & /@ Range@ 20, PrimeQ@# &]
%o (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
%Y Cf. A000670.
%K nonn,more
%O 1,1
%A _Amiram Eldar_, Jul 28 2017
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