A175600 Primes of form 4k+1 where k is a Pythagorean prime.

53, 149, 293, 389, 773, 1109, 1493, 1637, 1733, 2309, 2693, 2837, 3413, 3989, 4133, 4373, 4517, 5189, 5717, 5813, 6197, 6389, 7013, 7109, 8069, 8117, 9173, 9749, 10709, 10853, 11813, 12149, 12197, 12437, 12917, 13829, 13877, 14549, 15077, 15173

Offset

1,1

Comments

"Double-Pythagorean" primes: primes of form 4k+1 with k prime of form 4m+1.

All terms are congruent to 5 modulo 48. - Zak Seidov, Jun 05 2014

Links

Table of n, a(n) for n=1..40.

Example

53 = A002144(7) = 4*13 + 1, 13 = A002144(2);
149 = A002144(16) = 4*37 + 1, 37 = A002144(5).

Mathematica

se=Select[Range[5, 100000, 4], PrimeQ]; (* se=A002144 *)
se2=Select[se, MemberQ[se, (#-1)/4]&]
(* (se2-1)/4 = intersection (A005098, A002144) *)

Crossrefs

Cf. A002144 (Pythagorean primes: primes of form 4n+1), A005098 (Numbers n such that 4n+1 is prime).

Sequence in context: A161611 A251076 A142043 * A142417 A217718 A044385

Adjacent sequences: A175597 A175598 A175599 * A175601 A175602 A175603

Keyword

nonn

Author

Zak Seidov, Jul 22 2010

Status

approved