A097159 Smallest prime p such that the maximum run length of consecutive positive quadratic residues modulo p is n.

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, 1305511, 298483, 422231, 2495567, 3205777, 1523707, 701399, 6175987, 366791

Offset

1,1

Links

Table of n, a(n) for n=1..42.

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}]

Crossrefs

Cf. A002307, A025046, A097160, A097161, A129201.

Sequence in context: A344141 A344142 A338340 * A139603 A141183 A308724

Adjacent sequences: A097156 A097157 A097158 * A097160 A097161 A097162

Keyword

nonn

Author

Robert G. Wilson v, Jul 28 2004

Extensions

a(21)-a(33), a(35)-a(36), a(40), a(42) from T. D. Noe, Apr 03 2007

Name modified by and a(34), a(37)-a(39), a(41) from Jinyuan Wang, Jan 16 2026

Status

approved