A239061 Number of integers x, 1 <= x <= n, such that x^x == 1 (mod n).

1, 1, 2, 1, 2, 1, 2, 1, 2, 1, 3, 1, 5, 2, 4, 1, 4, 1, 4, 1, 3, 3, 2, 1, 2, 3, 2, 2, 4, 1, 3, 1, 5, 1, 6, 1, 3, 2, 4, 1, 5, 1, 6, 3, 5, 1, 2, 1, 4, 1, 6, 2, 3, 1, 5, 2, 3, 3, 3, 1, 5, 3, 3, 1, 9, 2, 5, 1, 5, 2, 4, 1, 5, 3, 5, 3, 10, 1, 5, 1, 2, 1, 3, 1, 10, 3

Offset: 1

Author

José María Grau Ribas, Mar 09 2014

Keywords

• nonn

Links

• Giovanni Resta, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A239062, A239063 (indices of 1's).

Programs

Mathematica

gg1[n_] := Sum[If[PowerMod[x, x, n] == Mod[1, n], 1, 0], {x, n}];Array[gg1,200]