A126332 Numbers k such that 10k + 13 is prime.
0, 1, 3, 4, 6, 7, 9, 10, 15, 16, 18, 21, 22, 25, 27, 28, 30, 34, 36, 37, 42, 43, 45, 49, 51, 55, 58, 60, 63, 64, 66, 67, 72, 73, 76, 81, 84, 85, 87, 94, 97, 100, 102, 105, 108, 109, 111, 114, 115, 118, 120, 121, 127, 129, 136, 141, 142, 144, 147, 148, 151, 153, 154, 157
Offset: 1
Examples
For k = 100, 10*k + 13 = 1013 (prime).
Programs
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Magma
[n: n in [0..1000] | IsPrime(10*n + 13)]; // Vincenzo Librandi, Nov 23 2010
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Mathematica
Select[Range[0,157],PrimeQ[10#+13]&] (* James C. McMahon, Dec 25 2024 *)
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PARI
is(n)=isprime(10*n+13) \\ Charles R Greathouse IV, Jun 13 2017
Formula
a(k) = A102338(k+1) - 1. - R. J. Mathar, Jul 08 2009