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A102700
Numbers k such that 10*k + 9 is prime.
10
1, 2, 5, 7, 8, 10, 13, 14, 17, 19, 22, 23, 26, 34, 35, 37, 38, 40, 41, 43, 44, 47, 49, 50, 56, 59, 61, 65, 70, 71, 73, 76, 80, 82, 83, 85, 91, 92, 100, 101, 103, 104, 106, 110, 112, 122, 124, 125, 127, 128, 131, 139, 140, 142, 143, 145, 148, 149, 154, 155, 157, 160, 161
OFFSET
1,2
LINKS
Chris Caldwell, The first 1,000 primes.
EXAMPLE
10*1 + 9 = 19 (prime);
10*40 + 9 = 409 (prime);
10*70 + 9 = 709 (prime).
MATHEMATICA
Select[Range[0, 170], PrimeQ[10# + 9] &] (* Ray Chandler, Nov 07 2006 *)
PROG
(Magma) [n: n in [0..3000]| IsPrime(10*n+9)]; // Vincenzo Librandi, Apr 06 2011
(PARI) is(n)=isprime(10*n+9) \\ Charles R Greathouse IV, Feb 17 2017
CROSSREFS
Sequence in context: A343301 A034028 A268272 * A095371 A047481 A372325
KEYWORD
base,nonn
AUTHOR
Parthasarathy Nambi, Feb 04 2005
EXTENSIONS
Edited and extended by Ray Chandler, Nov 07 2006
STATUS
approved