A099007 - OEIS

A099007

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

3, 19, 47, 139, 367, 467, 839, 1319, 1699, 1907, 3407, 4003, 4987, 6079, 7703, 10499, 11527, 13159, 16747, 17387, 19379, 23687, 25219, 26003, 30103, 32707, 33599, 35419, 38239, 44203, 50599, 53959, 55103, 57427, 62219, 69767, 72379, 76387

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OFFSET

1,1

COMMENTS

All terms are == 3 (mod 4).

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

EXAMPLE

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

MATHEMATICA

Select[Table[6n^2-2n-1, {n, 0, 2000}], PrimeQ] (* Vincenzo Librandi, Jul 17 2012 *)

PROG

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

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

CROSSREFS

Cf. A098828.

Sequence in context: A162905 A201875 A063553 * A023280 A054697 A214883

Adjacent sequences: A099004 A099005 A099006 * A099008 A099009 A099010

KEYWORD

nonn,easy

AUTHOR

Giovanni Teofilatto, Nov 07 2004

EXTENSIONS

Edited, corrected and extended by Klaus Brockhaus, Nov 12 2004

STATUS

approved