A139889 Primes of the form 5x^2+42y^2.

5, 47, 167, 173, 293, 383, 503, 647, 677, 773, 797, 887, 983, 1013, 1223, 1277, 1487, 1613, 1637, 1823, 1847, 1973, 2063, 2357, 2477, 2663, 2687, 2693, 2903, 2957, 3023, 3167, 3407, 3527, 3533, 3797, 3863, 4007, 4133, 4157, 4373, 4493, 4583

Offset

1,1

Comments

Discriminant=-840. See A139827 for more information.

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)

Formula

The primes are congruent to {5, 47, 143, 167, 173, 293, 383, 437, 503, 647, 677, 773, 797} (mod 840).

Mathematica

QuadPrimes2[5, 0, 42, 10000] (* see A106856 *)

Prog

(Magma) [ p: p in PrimesUpTo(5000) | p mod 840 in {5, 47, 143, 167, 173, 293, 383, 437, 503, 647, 677, 773, 797}]; // Vincenzo Librandi, Jul 30 2012

Crossrefs

Sequence in context: A229613 A335737 A277607 * A134327 A122501 A362430

Adjacent sequences: A139886 A139887 A139888 * A139890 A139891 A139892

Keyword

nonn,easy

Author

T. D. Noe, May 02 2008

Status

approved