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Numbers n such that 1 + 0!*1!*2!*...*n! is prime.
1

%I #5 Mar 30 2012 17:36:39

%S 0,1,2,3,7,14

%N Numbers n such that 1 + 0!*1!*2!*...*n! is prime.

%C Any additional terms are greater than 115 with the next prime having 9744 or more digits.

%o (PARI) pr=1; for(n=0,115, pr=pr*n!; if(isprime(pr+1), print1(n,",")))

%Y Cf. A073828 (corresponding primes), A000178 (superfactorials), A019515.

%K nonn

%O 1,3

%A _Rick L. Shepherd_, Aug 16 2002