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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
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
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
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Jun 24 2004
STATUS
approved