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Numbers n such that 168n+31 is prime.
1

%I #15 Sep 08 2022 08:45:33

%S 0,1,2,6,9,11,14,15,16,17,20,21,22,25,27,29,32,34,36,37,45,46,47,49,

%T 50,51,54,56,60,66,67,71,76,77,82,84,86,89,91,94,95,100,102,106,111,

%U 114,117,119,121,125,130,131,134,141,142,144,145,154,157,164,165,166,167

%N Numbers n such that 168n+31 is prime.

%H Zak Seidov, <a href="/A139639/b139639.txt">Table of n, a(n) for n = 1..1000.</a>

%F a(n) = (A137657(n)-31)/168 = (A137658(n)-1)/7 = (A137659(n)-1)/24.

%t Select[Range[0, 500], PrimeQ[168 # + 31] &] (* _Vincenzo Librandi_, May 23 2014 *)

%o (Magma) [n: n in [0..500] | IsPrime(168*n+31)]; // _Vincenzo Librandi_, Nov 24 2010

%o (PARI) is(n)=isprime(168*n+31) \\ _Charles R Greathouse IV_, Jun 13 2017

%Y Cf. A137657, A137658, A137659.

%K nonn,easy

%O 1,3

%A _Zak Seidov_, Apr 28 2008