A139650 Primes of the form x^2 + 190*y^2.

191, 199, 239, 271, 311, 359, 479, 631, 719, 761, 769, 809, 881, 919, 929, 1031, 1049, 1151, 1201, 1279, 1289, 1489, 1559, 1601, 1721, 1759, 1831, 1871, 1879, 1999, 2039, 2129, 2239, 2281, 2399, 2441, 2551, 2591, 2609, 2671, 2791, 2969

Offset: 1

Author

T. D. Noe, Apr 29 2008

Keywords

• nonn
• easy

Comments

Discriminant = -760.

The primes are congruent to {1, 9, 39, 49, 81, 111, 119, 121, 159, 161, 169, 191, 199, 201, 239, 271, 289, 311, 321, 329, 351, 359, 391, 441, 479, 481, 511, 519, 529, 609, 631, 671, 681, 689, 719, 729} (mod 760).

Links

• Vincenzo Librandi and Ray Chandler, Table of n, a(n) for n = 1..10000 (first 1000 terms from Vincenzo Librandi).
• N. J. A. Sloane et al., Binary Quadratic Forms and OEIS (Index to related sequences, programs, references)

Programs

Magma

k:=190; [p: p in PrimesUpTo(3000) | NormEquation(k, p) eq true]; // Bruno Berselli, Jun 01 2016

Mathematica

QuadPrimes2[1, 0, 190, 10000] (* see A106856 *)