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Numbers n such that 4*n^3 + 1 is prime.
8

%I #24 Feb 17 2017 14:55:32

%S 1,3,4,7,9,10,19,25,34,37,39,42,49,54,55,72,73,78,85,87,93,94,102,108,

%T 109,118,138,142,147,157,160,165,168,175,192,195,202,210,214,220,228,

%U 232,243,247,249,250,252,253,258,267,273,274,279,289,297

%N Numbers n such that 4*n^3 + 1 is prime.

%C For any n in this sequence, 3*(4*n^3 + 1) has the same nonzero digits as its prime factors in base 2n. - _Ely Golden_, Dec 12 2016

%H Ely Golden, <a href="/A115104/b115104.txt">Table of n, a(n) for n = 1..1000</a>

%e If n=94 then (4*n^3 + 1) = 3322337 (prime).

%t Select[Range[300], PrimeQ[4*#^3 + 1] &] (* _Stefan Steinerberger_, Mar 04 2006 *)

%o (PARI) is(n)=isprime(4*n^3+1) \\ _Charles R Greathouse IV_, Feb 17 2017

%Y Cf. A001912. See A199307 for the actual primes.

%Y See also A199364, A199365, A199366, A199367, A199368, A199369.

%K nonn

%O 1,2

%A _Parthasarathy Nambi_, Mar 02 2006

%E More terms from _Stefan Steinerberger_, Mar 04 2006