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A256811
Primes p such that (p^2+2)/3 and (p^4+2)/3 are prime.
1
37, 521, 881, 1619, 2053, 2213, 2341, 3527, 3637, 3727, 4157, 5147, 7019, 10009, 10891, 12277, 14741, 15913, 16273, 17747, 18757, 24499, 25307, 25577, 26209, 27073, 31481, 31517, 32833, 35083, 36739, 36791, 39079, 40231, 40949, 41039, 42013, 42461, 42767, 47917
OFFSET
1,1
LINKS
EXAMPLE
a(1) = 37; (37^2 + 2)/3 = 457; (37^4 + 2)/3 = 624721; all three are prime.
MATHEMATICA
Select[Prime[Range[10^4]], PrimeQ[(#^2 + 2)/3] && PrimeQ[(#^4 + 2)/3] &]
PROG
(PARI) forprime(p=1, 10^5, if(!((p^2+2)%3)&&!((p^4+2)%3)&&isprime((p^2+2)/3)&&isprime((p^4+2)/3), print1(p, ", "))) \\ Derek Orr, Apr 16 2015
(Magma) [p: p in PrimesUpTo(5*10^4) | IsPrime((p^2+2) div 3) and IsPrime((p^4+2) div 3 )]; // Vincenzo Librandi, Apr 20 2015
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
K. D. Bajpai, Apr 15 2015
STATUS
approved