A097159 Smallest prime p such that there are n consecutive quadratic residues mod p.

2, 7, 11, 19, 43, 67, 83, 131, 283, 277, 467, 479, 1907, 1607, 2543, 1559, 5443, 5711, 6389, 14969, 25703, 10559, 20747, 52057, 136223, 90313, 162263, 18191, 167107, 31391, 376589, 607153, 671947

Offset: 1

Author

Robert G. Wilson v, Jul 28 2004

Keywords

• nonn

Comments

Additional terms less than 10^6: a(35)=298483, a(36)=422231, a(40)=701399 and a(42)=366791. - T. D. Noe, Apr 03 2007

Examples

			a(22)=10559, a(23)=20747 & a(28)=18191.
		

Crossrefs

Cf. A002307, A097160, A097161.

Cf. A129201.

Programs

Mathematica

f[l_, a_] := Module[{A = Split[l], B}, B = Last[ Sort[ Cases[A, x : {a ..} :> { Length[x], Position[A, x][[1, 1]] }] ]]; {First[B], Length[ Flatten[ Take[A, Last[B] - 1]]] + 1}]; g[n_] := g[n] = f[ JacobiSymbol[ Range[ Prime[n] - 1], Prime[n]], 1][[1]]; g[1] = 1; a = Table[0, {30}]; Do[b = g[n]; If[ a[[b]] < 31 && a[[b]] == 0, a[[b]] = n; Print[b, " = ", Prime[n]]], {n, 2555}]

Extensions

More terms from T. D. Noe, Apr 03 2007