A107308 Numbers k such that (29*k - 31) is prime.

12, 16, 18, 22, 30, 36, 40, 42, 46, 48, 60, 70, 82, 88, 90, 96, 102, 112, 118, 120, 126, 130, 132, 148, 156, 166, 172, 180, 190, 196, 198, 202, 228, 238, 246, 250, 256, 258, 268, 280, 282, 286, 300, 316, 330, 340, 342, 348, 352, 382, 390, 406, 408, 420, 426

Offset: 1

Author

Parthasarathy Nambi, May 20 2005

Keywords

• nonn
• easy

Comments

29 and 31 are twin primes.

Examples

			If k=48, then 29*k - 31 = 1361 (prime).
		

Links

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

Crossrefs

Cf. A142003 (the resulting primes).

Programs

Magma

[n: n in [2..100000] | IsPrime(29*n - 31)]; // Vincenzo Librandi, Nov 13 2010

Mathematica

Select[Range[2,500],PrimeQ[29#-31]&] (* Harvey P. Dale, Apr 22 2016 *)

PARI

is(n)=isprime((29*n-31)) \\ Charles R Greathouse IV, Jun 12 2017