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A231549
Least k>0 such that k!*n!+1 is a prime, or 0 if no such k exists.
2
1, 1, 1, 4, 2, 8, 3, 3, 3, 4, 1, 2, 3, 5, 8, 4, 10, 2, 11, 9, 5, 5, 7, 3, 14, 18, 1, 40, 24, 5, 5, 18, 8, 20, 2, 49, 1, 3, 5, 28, 1, 17, 38, 27, 11, 16, 10, 3, 24, 270, 2, 45, 2, 15, 175, 64, 17, 6, 4, 3, 8, 18, 13, 17, 65, 32, 12, 7, 72, 13, 21, 33, 1, 24, 36, 76, 1
OFFSET
1,4
COMMENTS
Indices of 1's: A002981.
MATHEMATICA
Table[k = 1; While[! PrimeQ[k!*n! + 1], k++]; k, {n, 100}] (* T. D. Noe, Nov 18 2013 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Alex Ratushnyak, Nov 15 2013
STATUS
approved