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A191089 Least prime p such that the first n primes are not squares mod p. 2
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 (list; graph; refs; listen; history; text; internal format)
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.

LINKS

Table of n, a(n) for n=1..30.

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

Cf. A001992, A147972, A191088.

Sequence in context: A216085 A219018 A191088 * A199345 A062633 A240559

Adjacent sequences:  A191086 A191087 A191088 * A191090 A191091 A191092

KEYWORD

nonn

AUTHOR

T. D. Noe, May 25 2011

EXTENSIONS

a(16)-a(30) from Charles R Greathouse IV, Oct 10 2011

STATUS

approved

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Last modified April 5 20:17 EDT 2020. Contains 333260 sequences. (Running on oeis4.)