%I #7 Sep 08 2022 08:45:15

%S 3,19,47,139,367,467,839,1319,1699,1907,3407,4003,4987,6079,7703,

%T 10499,11527,13159,16747,17387,19379,23687,25219,26003,30103,32707,

%U 33599,35419,38239,44203,50599,53959,55103,57427,62219,69767,72379,76387

%N Primes of the form 6n^2 - 2n - 1.

%C All terms are == 3 (mod 4).

%H Vincenzo Librandi, <a href="/A099007/b099007.txt">Table of n, a(n) for n = 1..1000</a>

%e For n = 2 we have 6*2^2 - 2*2 -1 = 19.

%t Select[Table[6n^2-2n-1,{n,0,2000}],PrimeQ] (* _Vincenzo Librandi_, Jul 17 2012 *)

%o (PARI) for(k=1,120,if(isprime(p=6*k^2-2*k-1),print1(p,",")))

%o (Magma) [a: n in [0..250] | IsPrime(a) where a is 6*n^2 - 2*n - 1]; // _Vincenzo Librandi_, Jul 17 2012

%Y Cf. A098828.

%K nonn,easy

%O 1,1

%A _Giovanni Teofilatto_, Nov 07 2004

%E Edited, corrected and extended by _Klaus Brockhaus_, Nov 12 2004