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A092581
a(n) is the least prime such that a(n-1) is a quadratic non-residue of a(n).
2
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
1,1
REFERENCES
Paulo Ribenboim, "The Little Book of Big Primes", Springer-Verlag, 1991, p. 28.
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)
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 *)
CROSSREFS
Cf. A034794.
Sequence in context: A078334 A108696 A215642 * A362527 A130807 A338577
KEYWORD
nonn
AUTHOR
Gary W. Adamson, Feb 29 2004
EXTENSIONS
More terms from Robert G. Wilson v, Mar 16 2004
a(17) corrected by T. D. Noe, Aug 28 2007
STATUS
approved