A206589 Number of solutions (n,k) of p(k+1)=p(n+1) (mod n), where 1<=k

1, 0, 2, 1, 2, 1, 1, 1, 1, 0, 3, 1, 2, 1, 2, 0, 2, 0, 2, 1, 2, 1, 1, 0, 0, 1, 1, 0, 4, 1, 2, 2, 2, 1, 1, 1, 1, 1, 3, 1, 3, 1, 1, 2, 1, 0, 3, 1, 1, 1, 1, 0, 2, 1, 2, 2, 1, 1, 4, 0, 1, 1, 0, 0, 2, 0, 2, 2, 3, 0, 4, 1, 2, 2, 1, 1, 3, 1, 2, 1, 2, 1, 3, 1, 3, 2, 3, 1, 3, 0, 1, 0, 2, 1, 2, 0, 2, 0, 2

Offset: 2

Author

Clark Kimberling, Feb 09 2012

Keywords

• nonn

Comments

Related to A206588, which includes differences p-2.

Examples

			For k=1 to 5, the numbers p(7)-p(k+1) are 14,12,10,6,4, so that a(6)=2.
		

Crossrefs

Cf. A206588.

Programs

Mathematica

f[n_,k_]:=If[Mod[Prime[n+1]-Prime[k+1],n]==0,1,0];
t[n_] := Flatten[Table[f[n, k], {k, 1, n - 1}]]
a[n_] := Count[Flatten[t[n]], 1]
Table[a[n], {n, 2, 120}]  (* A206589 *)