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A097143
a(n) is the least prime greater than a(n-1) such that n is a quadratic residue mod p.
2
2, 7, 11, 13, 19, 23, 29, 31, 37, 41, 43, 47, 53, 61, 67, 71, 83, 89, 101, 109, 127, 137, 173, 191, 193, 197, 227, 233, 239, 241, 251, 257, 263, 269, 271, 277, 293, 313, 317, 347, 349, 353, 383, 389, 401, 409, 419, 421, 431, 433, 439, 443, 449, 457, 463, 479
OFFSET
1,1
COMMENTS
a(10^n): 2,41,1229,16693,220721,2734801,32393839,..., .
Conjecture: Lim_n->Inf a(n)/A097144(n) = 1 <==> a(P_2n).
LINKS
Eric Weisstein's World of Mathematics, Quadratic Residue.
MATHEMATICA
a[1] = 2; a[n_] := a[n] = Block[{k = PrimePi[ a[n - 1]] + 1}, While[ JacobiSymbol[n, Prime[k]] != 1, k++ ]; Prime[k]]; Table[ a[n], {n, 20}]
CROSSREFS
Cf. A097152. Complement of A097144.
Sequence in context: A191052 A338173 A138889 * A038897 A161681 A020583
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Jul 26 2004
STATUS
approved