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A037083
Numbers n such that n!!! + 1 is prime (0 is included by convention).
18
0, 1, 2, 4, 5, 6, 7, 9, 10, 11, 17, 24, 29, 39, 40, 57, 58, 59, 91, 155, 175, 245, 359, 372, 597, 864, 977, 1077, 1327, 2076, 4798, 4975, 10830, 13453, 15472, 15948, 16116, 16681, 18037, 21725, 22326, 24753, 28565, 32659, 46487, 50649, 51393, 80069, 95493
OFFSET
1,3
COMMENTS
n!!! = n(n-3)(n-6)(n-9)...
The search for multifactorial primes started by Ray Ballinger is now continued by a team of volunteers on the website of Ken Davis (see link).
CROSSREFS
Cf. A007661 (triple factorials), A084438, A037082.
Sequence in context: A376956 A288866 A084437 * A188033 A187485 A039052
KEYWORD
nonn
EXTENSIONS
More terms from Steven Harvey
Corrected and extended by Hugo Pfoertner, Jun 25 2003
More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 03 2008
Edited by N. J. A. Sloane, Jan 14 2008
STATUS
approved