A153781 Numbers n such that n^2+13n+23 is prime.

0, 1, 2, 3, 5, 6, 7, 8, 14, 15, 16, 19, 20, 24, 27, 28, 34, 36, 37, 40, 41, 42, 44, 45, 47, 49, 57, 59, 62, 64, 66, 68, 71, 72, 73, 78, 84, 85, 86, 90, 96, 103, 105, 106, 110, 117, 119, 122, 124, 129, 132, 133, 136, 141, 150, 154, 156, 157, 163, 168, 169, 174

Offset: 1

Author

Vincenzo Librandi, Jan 03 2009

Keywords

• nonn
• easy

Links

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

Crossrefs

Cf. A144561.

Programs

Magma

[n: n in [0..200]| IsPrime(n^2+13*n+23)]; // Vincenzo Librandi, Jul 31 2012

Mathematica

Select[Range[0,900], PrimeQ[#^2 + 13 # + 23] &] (* Vincenzo Librandi, Jul 31 2012 *)

PARI

is(n)=isprime(n^2+13*n+23) \\ Charles R Greathouse IV, May 22 2017