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

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, 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, 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

Offset

1,1

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Maple

g:= proc(n) local p;
  p:= 1;
  do
    p:= nextprime(p);
    if numtheory:-quadres(n, p) = -1 then return p fi
  od
end proc:
map(g, select(isprime, [seq(i, i=5..10000, 8)])); # Robert Israel, Apr 17 2023

Mathematica

f[n_] := Block[{k = 2}, While[ JacobiSymbol[n, Prime[k]] == 1, k++ ]; Prime[k]]; f /@ Select[ Prime[ Range[435]], Mod[ #, 8] == 5 &]

Crossrefs

Cf. A094928, A096633, A096635, A096638.

Sequence in context: A152050 A103506 A094929 * A105439 A142972 A020765

Adjacent sequences: A096631 A096632 A096633 * A096635 A096636 A096637

Keyword

nonn

Author

Robert G. Wilson v, Jun 24 2004

Status

approved