A102731 Numbers k such that 11*k + 23 is prime.

0, 4, 6, 16, 28, 30, 34, 36, 40, 54, 58, 60, 64, 76, 78, 84, 88, 90, 100, 114, 118, 126, 130, 144, 160, 168, 180, 186, 190, 196, 204, 208, 210, 214, 216, 228, 240, 244, 246, 258, 264, 268, 274, 286, 288, 294, 298, 300, 306, 310, 316, 328, 334, 336, 348, 354, 364

Offset: 1

Author

Parthasarathy Nambi, Feb 07 2005

Keywords

• nonn
• easy

Examples

			If k=0, then 11*0 + 23 = 23 (prime).
If k=54, then 11*54 + 23 = 617 (prime).
If k=114, then 11*114 + 23 = 1277 (prime).
		

Links

• Harvey P. Dale, Table of n, a(n) for n = 1..1000

Programs

Magma

[n: n in [0..1000] | IsPrime(11*n + 23)]; // Vincenzo Librandi, Nov 17 2010

Mathematica

Select[Range[0,400],PrimeQ[11#+23]&] (* Harvey P. Dale, Oct 17 2011 *)

PARI

is(n)=isprime(11*n+23) \\ Charles R Greathouse IV, Jun 12 2017

Formula

a(n) = A102656(n) - 2. - R. J. Mathar, Jul 08 2009