A228926 Sum(m^(n+1), m=1...n-1) modulo n.

0, 1, 2, 0, 0, 3, 0, 0, 6, 5, 0, 0, 0, 7, 7, 0, 0, 9, 0, 0, 14, 11, 0, 0, 0, 13, 18, 0, 0, 15, 0, 0, 22, 17, 23, 0, 0, 19, 26, 0, 0, 21, 0, 0, 30, 23, 0, 0, 0, 25, 34, 0, 0, 27, 44, 0, 38, 29, 0, 0, 0, 31, 42, 0, 0, 33, 0, 0, 46, 35, 0, 0, 0, 37, 35, 0, 66

Offset: 1

Author

José María Grau Ribas, Sep 08 2013

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 1..16384

Crossrefs

Cf. A121706, A228919, A204187.

Programs

Mathematica

f[n_] := Mod[Sum[PowerMod[i,n+1,n], {i, 1, n}], n]; Table[f[n], {n, 100}]

PARI

a(n)=lift(sum(m=1,n-1,Mod(m,n)^(n+1))) \\ Charles R Greathouse IV, Dec 27 2013

Formula

a(n) = A121706(n) mod (n-1). - T. D. Noe, Sep 16 2013