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A139639
Numbers n such that 168n+31 is prime.
1
0, 1, 2, 6, 9, 11, 14, 15, 16, 17, 20, 21, 22, 25, 27, 29, 32, 34, 36, 37, 45, 46, 47, 49, 50, 51, 54, 56, 60, 66, 67, 71, 76, 77, 82, 84, 86, 89, 91, 94, 95, 100, 102, 106, 111, 114, 117, 119, 121, 125, 130, 131, 134, 141, 142, 144, 145, 154, 157, 164, 165, 166, 167
OFFSET
1,3
FORMULA
a(n) = (A137657(n)-31)/168 = (A137658(n)-1)/7 = (A137659(n)-1)/24.
MATHEMATICA
Select[Range[0, 500], PrimeQ[168 # + 31] &] (* Vincenzo Librandi, May 23 2014 *)
PROG
(Magma) [n: n in [0..500] | IsPrime(168*n+31)]; // Vincenzo Librandi, Nov 24 2010
(PARI) is(n)=isprime(168*n+31) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Zak Seidov, Apr 28 2008
STATUS
approved