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Primes congruent to 2 or 8 modulo 15.
1

%I #12 Jun 10 2021 16:56:48

%S 2,17,23,47,53,83,107,113,137,167,173,197,227,233,257,263,293,317,347,

%T 353,383,443,467,503,557,563,587,593,617,647,653,677,683,743,773,797,

%U 827,857,863,887,947,953,977,983

%N Primes congruent to 2 or 8 modulo 15.

%C This sequence is the complement of A033212 (primes congruent to 1 or 4 mod(15)) relative to the primes p with Jacobi(p|15) = +1 (A191018).

%C There is neither a solution x of the congruence x^2 == a(n) (mod 3) nor of x^2 == a(n) (mod 5) (the Legendre symbols are -1 in both cases, and Jacobi(a(n)|15) = +1).

%t Select[Range[1000], PrimeQ[#] && MemberQ[{2, 8}, Mod[#, 15]] &] (* _Amiram Eldar_, May 20 2021 *)

%Y Cf. A033212, A106859 (with 3 and 5), A191018.

%K nonn,easy

%O 1,1

%A _Wolfdieter Lang_, May 20 2021