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A260352
Numbers n such that both 2*n^2+11 and 2*(n+1)^2+11 are prime.
2
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 15, 18, 19, 23, 28, 29, 30, 41, 42, 49, 62, 69, 70, 94, 95, 108, 123, 136, 145, 151, 152, 189, 190, 204, 212, 215, 223, 227, 276, 277, 278, 281, 290, 291, 294, 314, 328, 342, 353, 367, 368, 372, 405, 410, 436, 488, 497
OFFSET
1,3
COMMENTS
Both n and n+1 are terms in A092968.
MATHEMATICA
Select[Range[0, 600], PrimeQ[2 #^2 + 11] && PrimeQ[2 (# + 1)^2 + 11] &] (* Vincenzo Librandi, Jul 26 2015 *)
PROG
(PARI) isok(n) = isprime(2*n^2+11) && isprime(2*(n+1)^2+11); \\ Michel Marcus, Jul 26 2015
(Magma) [n: n in [0..600]| IsPrime( 2*n^2+11) and IsPrime(2*(n+1)^2+11)]; // Vincenzo Librandi, Jul 26 2015
CROSSREFS
Cf. A092968.
Sequence in context: A328933 A032978 A197181 * A049101 A287336 A048406
KEYWORD
nonn,easy
AUTHOR
Zak Seidov, Jul 23 2015
STATUS
approved