OFFSET
1,3
EXAMPLE
10*1 + 7 = 17 (prime);
10*48 + 7 = 487 (prime);
10*99 + 7 = 997 (prime).
MATHEMATICA
Select[Range[0, 170], PrimeQ[10# + 7] &] (* Ray Chandler, Nov 07 2006 *)
PROG
(Magma) [n: n in [0..3000]| IsPrime(10*n+7)]; // Vincenzo Librandi, Apr 06 2011
(PARI) is(n)=isprime(10*n+7) \\ Charles R Greathouse IV, Feb 17 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
Parthasarathy Nambi, Feb 20 2005
EXTENSIONS
Edited and extended by Ray Chandler, Nov 07 2006
STATUS
approved