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%I #9 May 13 2020 19:01:25
%S 2,7,11,13,19,23,29,31,37,41,43,47,53,61,67,71,83,89,101,109,127,137,
%T 173,191,193,197,227,233,239,241,251,257,263,269,271,277,293,313,317,
%U 347,349,353,383,389,401,409,419,421,431,433,439,443,449,457,463,479
%N a(n) is the least prime greater than a(n-1) such that n is a quadratic residue mod p.
%C a(10^n): 2,41,1229,16693,220721,2734801,32393839,..., .
%C Conjecture: Lim_n->Inf a(n)/A097144(n) = 1 <==> a(P_2n).
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/QuadraticResidue.html">Quadratic Residue</a>.
%t 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}]
%Y Cf. A097152. Complement of A097144.
%K nonn
%O 1,1
%A _Robert G. Wilson v_, Jul 26 2004
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