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A195131
Numbers k such that 666k-1 is prime.
1
3, 4, 5, 10, 14, 17, 18, 19, 25, 27, 30, 33, 34, 38, 44, 49, 52, 54, 55, 59, 63, 67, 69, 70, 72, 80, 89, 94, 97, 98, 102, 103, 104, 105, 107, 110, 128, 130, 132, 135, 140, 149, 154, 157, 158, 163, 174, 175, 177, 185, 187, 188, 199, 203, 220, 223, 224, 228, 237, 238, 240, 245, 249, 257, 258, 262, 265, 268, 270, 279, 280, 287, 290, 292
OFFSET
1,1
LINKS
EXAMPLE
a(1)=3 since 3*666-1 = 1997 = A063472(1) is prime, and the smallest prime to be of that form.
K=139*666^178850 is also a member of this sequence, since 139*666^178851-1 is prime (cf. link).
PROG
(PARI) for(k=1, 999, ispseudoprime(k*666-1)&print1(k", "))
CROSSREFS
KEYWORD
nonn
AUTHOR
M. F. Hasler, Sep 09 2011
STATUS
approved