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A175600 Primes of form 4n+1 with n = pythagorean prime. 2
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

"Double-pythagorean" primes: primes of form 4n+1 with n = 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

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Last modified August 20 03:34 EDT 2017. Contains 290823 sequences.