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%I #11 Sep 08 2022 08:45:31
%S 2,4,8,10,12,14,18,20,22,26,30,34,44,46,58,66,68,70,74,76,78,84,90,96,
%T 100,106,108,110,120,128,134,140,146,152,154,156,158,162,164,168,174,
%U 184,186,188,196,200,202,210,216,228,232,238,250,252,260,262,264,268
%N Numbers n such that 7*n^2 + 1 is prime.
%e If n=2 then 7*n^2 + 1 = 29 (prime).
%e If n=100 then 7*n^2 + 1 = 70001 (prime).
%t Select[Range[300], PrimeQ[7*#^2 + 1] &] (* _Stefan Steinerberger_, Jan 02 2008 *)
%o (Magma) [ n: n in [0..500] | IsPrime(7*n^2 + 1) ] // _Vincenzo Librandi_, Jan 31 2011
%o (PARI) is(n)=isprime(7*n^2+1) \\ _Charles R Greathouse IV_, Jun 13 2017
%Y Cf. A111051.
%K nonn,easy
%O 1,1
%A _Parthasarathy Nambi_, Nov 05 2007
%E More terms from _Stefan Steinerberger_, Jan 02 2008
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