A122159 Period of A002067 modulo prime(n).

1, 1, 8, 3, 10, 24, 32, 18, 22, 56, 30, 72, 80, 42, 23, 104, 29, 120, 66, 70, 144, 39, 41, 176, 192, 200, 51, 53, 216, 224, 63, 130, 272, 69, 296, 150, 312, 162, 166, 344, 178, 360, 95, 384, 392, 99, 105, 222, 226, 456, 464, 238, 480, 125, 512, 131, 536, 270, 552

Offset: 1

Author

N. J. A. Sloane, Aug 06 2008

Keywords

• nonn

Examples

			A002067 modulo 5 is 1, 1, 2, 2, 4, 4, 3, 3, 1, 1, 2, 2, 4, 4, 3, 3, 1, 1, ... with period 8.
		

Crossrefs

Cf. A002067, A122149.

Programs

Mathematica

max = 100; se = Series[InverseErf[2*x/Sqrt[Pi]], {x, 0, 2*max + 1}]; a[n_] := (2 n + 1)!/2^n*Coefficient[se, x, 2*n + 1]; A002067 = Table[a[n], {n, 0, max}]; period[lst_List] := Catch[lg = If[Length[lst] <= 5, 2, 5]; lst1 = lst[[1 ;; lg]]; km = Length[lst] - lg; Do[If[lst1 == lst[[k ;; k + lg - 1]], Throw[k - 1]]; If[k == km, Throw[0]], {k, 2, km}]]; Table[ period[Mod[A002067, Prime[n]] // Reverse] , {n, 1, 15}] (* Jean-François Alcover, Dec 17 2012 *)

Formula

a(n) = A122149(A000040(n)).

Extensions

a(9)-a(15) from Jean-François Alcover, Dec 17 2012

More terms from Jinyuan Wang, Jul 30 2022