cp's OEIS Frontend

A096634 Let p = n-th prime == 5 (mod 8) (A007521); a(n) = smallest prime q such that p is not a square mod q.

%I A096634 #11 Apr 18 2023 08:29:15
%S A096634 3,5,3,5,3,7,3,11,3,5,3,7,3,7,3,5,3,3,7,5,3,5,13,3,3,11,3,5,3,7,3,3,
%T A096634 13,5,5,3,3,3,7,5,5,3,5,3,7,3,7,5,3,5,3,5,3,5,3,3,3,11,11,5,3,13,5,3,
%U A096634 17,3,7,5,3,3,7,11,7,3,3,5,3,3,3,7,5,3,3,3,11,3,13,5,3,3,7,3,3,11,5,3,3,5,3
%N A096634 Let p = n-th prime == 5 (mod 8) (A007521); a(n) = smallest prime q such that p is not a square mod q.
%H A096634 Robert Israel, <a href="/A096634/b096634.txt">Table of n, a(n) for n = 1..10000</a>
%p A096634 g:= proc(n) local p;
%p A096634   p:= 1;
%p A096634   do
%p A096634     p:= nextprime(p);
%p A096634     if numtheory:-quadres(n,p) = -1 then return p fi
%p A096634   od
%p A096634 end proc:
%p A096634 map(g, select(isprime, [seq(i,i=5..10000,8)])); # _Robert Israel_, Apr 17 2023
%t A096634 f[n_] := Block[{k = 2}, While[ JacobiSymbol[n, Prime[k]] == 1, k++ ]; Prime[k]]; f /@ Select[ Prime[ Range[435]], Mod[ #, 8] == 5 &]
%Y A096634 Cf. A094928, A096633, A096635, A096638.
%K A096634 nonn
%O A096634 1,1
%A A096634 _Robert G. Wilson v_, Jun 24 2004