A174281 - OEIS

A174281

Primes p such that 20*p^2+32*p+13 is also prime.

2, 5, 7, 17, 19, 23, 29, 47, 73, 83, 89, 97, 107, 113, 127, 137, 149, 163, 197, 227, 229, 233, 239, 257, 269, 307, 359, 367, 373, 379, 439, 449, 557, 569, 619, 647, 673, 727, 739, 769, 797, 827, 877, 883, 919, 977, 983, 997, 1009, 1033, 1039, 1087, 1117, 1123

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

EXAMPLE

For p=2, 20*2^2+32*2+13=157; p=5, 20*5^2+32*5+13=673.

MATHEMATICA

Select[Prime[Range[200]], PrimeQ[20 #^2 + 32 # + 13]&] (* Vincenzo Librandi, Apr 16 2013 *)

PROG

(Magma) [p: p in PrimesUpTo(2000)| IsPrime(20*p^2+32*p+13)];

CROSSREFS