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A191089
Least prime p such that the first n primes are not squares mod p.
3
3, 5, 43, 43, 67, 67, 163, 163, 163, 163, 163, 163, 74093, 170957, 360293, 679733, 2004917, 2004917, 51599563, 51599563, 96295483, 96295483, 146161723, 1408126003, 1728061733, 1728061733, 1728061733, 1728061733, 1728061733, 1728061733
OFFSET
1,1
COMMENTS
That is, the first n primes are quadratic non-residues mod p. A less restrictive form of A001992. Sequence A191088 is similar, but allows p to be composite. See A147972 for the square version.
MATHEMATICA
Table[p = 2; While[Length[Select[Prime[Range[n]], JacobiSymbol[#, p] == -1 &]] < n, p = NextPrime[p]]; p, {n, 15}]
PROG
(PARI) q=2; forprime(k=3, 1e9, forprime(p=2, q, if(kronecker(p, k)>=0, next(2))); print1(k", "); q=nextprime(q+1); k--) \\ Charles R Greathouse IV, Oct 10 2011
CROSSREFS
KEYWORD
nonn
AUTHOR
T. D. Noe, May 25 2011
EXTENSIONS
a(16)-a(30) from Charles R Greathouse IV, Oct 10 2011
STATUS
approved