OFFSET
1,1
COMMENTS
See comments, references and links in A053760 = Smallest positive quadratic nonresidue modulo the n-th prime.
LINKS
Kevin J. McGown, On the second smallest prime non-residue, J. Number Theory, 133 (2013), 1289-1299.
EXAMPLE
The positive quadratic non-residues modulo prime(5) = 11 are 2, 6, 7, 8, 10, 11, ... and the second smallest prime among them is 7, so a(5) = 7.
MATHEMATICA
Table[p = Prime[n]; Part[ Select[ Range[p+1], JacobiSymbol[#, p] != 1 &], 2], {n, 1, 100}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Jonathan Sondow, May 02 2013
STATUS
approved