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A126961
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Primes p such that (3p)^2 + 2 is not prime.
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1
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2, 17, 23, 29, 31, 43, 47, 53, 59, 61, 67, 71, 89, 97, 109, 113, 127, 131, 137, 157, 163, 173, 179, 181, 193, 197, 199, 211, 223, 229, 239, 241, 257, 263, 271, 277, 281, 283, 293, 307, 313, 317, 331, 347, 349, 353, 359, 367, 373, 379, 383, 389, 397, 401, 409
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OFFSET
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1,1
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REFERENCES
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Garath A. Jones and Mary Jones, Elementary Number Theory, Springer - Verlag London, 1998; p. 35, Exercise 2.17.
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LINKS
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MATHEMATICA
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Select[Prime[Range[100]], ! PrimeQ[(3#)^2 + 2] &] (* Harvey P. Dale, Jun 14 2011 *)
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PROG
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(PARI) g(n) = forprime(x=0, n, y=9*x^2+2; if(!isprime(y), print1(x", ")))
(Magma) [p: p in PrimesUpTo(500) | not IsPrime(9*p^2+2)]; // Vincenzo Librandi, Apr 17 2013
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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