A092581 a(n) is the least prime such that a(n-1) is a quadratic non-residue of a(n).

2, 3, 5, 7, 11, 13, 19, 23, 31, 37, 43, 47, 59, 61, 67, 71, 79, 83, 89, 101, 103, 107, 109, 127, 131, 137, 149, 151, 157, 163, 167, 179, 181, 191, 199, 227, 229, 239, 251, 257, 263, 271, 277, 283, 307, 311, 331, 347, 349, 359, 367, 373, 379, 383, 409, 431, 439

Offset: 1

Author

Gary W. Adamson, Feb 29 2004

Keywords

• nonn

References

• Paulo Ribenboim, "The Little Book of Big Primes", Springer-Verlag, 1991, p. 28.

Links

• T. D. Noe, Table of n, a(n) for n=1..1000

Crossrefs

Cf. A034794.

Programs

Mathematica

first Needs[ "NumberTheory`NumberTheoryFunctions`" ] then f[n_] := Block[{k = PrimePi[n] + 1}, While[ JacobiSymbol[n, Prime[k]] == 1, k++ ]; Prime[k]]; NestList[f, 2, 56] (* Robert G. Wilson v, Mar 16 2004 *)

Formula

"If p>2 does not divide a and if there exists an integer b such that a is congruent to b^2 (mod p), then a is called a quadratic residue modulo p; otherwise, it is a nonquadratic residue modulo p". (p. 28, Ribenboim)

Extensions

More terms from Robert G. Wilson v, Mar 16 2004

a(17) corrected by T. D. Noe, Aug 28 2007