A111068 - OEIS

%I #20 Feb 09 2020 13:10:19

%S 1,3,7,11,13,15,17,27,29,35,41,43,45,49,53,55,59,63,71,81,91,95,105,

%T 111,119,123,129,141,143,155,171,181,183,197,199,207,209,217,221,237,

%U 241,249,251,253,263,277,283,297,309,315,323,325,337,349,357,363,365,371

%N Numbers k such that 3*k^2 + 16 is prime.

%H Daniel Starodubtsev, <a href="/A111068/b111068.txt">Table of n, a(n) for n = 1..10000</a>

%e If k=95 then 3*k^2 + 16 = 27091 (prime).

%p A111068:=n->`if`(isprime(3*n^2+16), n, NULL): seq(A111068(n), n=1..800); # _Wesley Ivan Hurt_, Jan 13 2017

%t Select[Range[0, 400], PrimeQ[3*#^2 + 16] &] (* _Stefan Steinerberger_, Mar 03 2006 *)

%o (PARI) is(n)=isprime(3*n^2+16) \\ _Charles R Greathouse IV_, May 22 2017

%Y Cf. A111069.

%K nonn

%O 1,2

%A _Parthasarathy Nambi_, Oct 08 2005

%E More terms from _Stefan Steinerberger_, Mar 03 2006