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A230809
Primes p of the form 60*n + 59 such that 2*p + 1 is also prime.
3
179, 239, 359, 419, 659, 719, 1019, 1439, 1499, 1559, 2039, 2339, 2399, 2459, 2699, 2819, 2939, 3299, 3359, 3539, 3779, 4019, 4919, 5039, 5279, 5399, 5639, 6899, 7079, 9059, 9419, 9479, 9539, 10799, 11519, 11579, 11699, 11939, 12119, 12899, 12959, 13619
OFFSET
1,1
COMMENTS
Primes p such that 2*p + 1 divides Lucas(p) and Mersenne(p).
LINKS
Eric Weisstein's World of Mathematics, Lucas Number
Eric Weisstein's World of Mathematics, Mersenne Number
FORMULA
A005384 INTERSECT A142799.
A002515 INTERSECT A215850.
EXAMPLE
179 is in the sequence since it is prime and 359 is a factor of both Lucas(179) and Mersenne(179) = 2^179 - 1.
PROG
(Magma) [p : p in [59..13619 by 60] | IsPrime(p) and IsPrime(2*p+1)];
(PARI) forstep(p=59, 13619, 60, if(isprime(p)&&isprime(2*p+1), print1(p, ", ")));
CROSSREFS
Subsequence of A142799, of A215850, and of A239548. Cf. A000032, A001348, A002515.
Sequence in context: A226928 A162164 A238893 * A335067 A142028 A146359
KEYWORD
nonn
AUTHOR
STATUS
approved