A176557 Primes of the form 7*x^2 - 5*y^2, where x and y are successive natural numbers.

7, 23, 43, 67, 127, 163, 347, 463, 743, 823, 907, 1087, 1283, 1607, 1723, 2503, 2647, 3767, 3943, 5923, 6143, 6367, 6827, 7547, 8563, 9643, 9923, 11083, 11383, 13267, 14947, 15647, 16363, 17467, 18223, 19387, 20183, 21407, 24847, 25747, 26203

Offset

1,1

Comments

a(n) is congruent 3 mod 4.

Primes of the form 2x^2+10x-5, x>=1. [From R. J. Mathar and Vincenzo Librandi, Apr 21 2010]

Links

Table of n, a(n) for n=1..41.

Crossrefs

Cf. A176470

Sequence in context: A375352 A319050 A031371 * A370643 A000353 A097149

Adjacent sequences: A176554 A176555 A176556 * A176558 A176559 A176560

Keyword

nonn

Author

Giovanni Teofilatto, Apr 20 2010

Extensions

More terms from R. J. Mathar and Vincenzo Librandi, Apr 21 2010

Status

approved