A256397 - OEIS

%I #17 Sep 08 2022 08:46:11

%S 17,23,41,47,71,89,113,137,167,191,233,239,257,263,281,311,353,359,

%T 383,401,431,449,479,503,521,569,593,599,617,641,647,719,743,761,809,

%U 839,857,863,881,887,911,929,953,977,983,1031,1049,1097,1103,1151,1193

%N Primes congruent to {17, 23} mod 24.

%C All these primes do not divide any number of the form 2^k + 3. Therefore, they are not in A256396.

%F A107181 UNION A134517.

%t Select[Prime@Range[196], MemberQ[{17, 23}, Mod[#, 24]] &]

%o (Magma) [p: p in PrimesUpTo(1193) | p mod 24 in {17, 23}];

%o (PARI) select(p->my(k=p%24); k==17||k==23, primes(1000)) \\ _Charles R Greathouse IV_, Jun 03 2015

%Y Cf. A107181, A134517, A256396.

%K nonn

%O 1,1

%A _Arkadiusz Wesolowski_, Jun 03 2015