A231565 - OEIS

%I #7 Jan 16 2014 10:08:17

%S 2,4,6,8,12,16,18,20,24,30,32,36,40,42,48,54,60,64,66,72,80,84,90,96,

%T 100,102,108,110,120,126,128,132,138,140,144,150,156,160,162,168,174,

%U 180,192,198,200,204,210,216,220,240,246,252,256,260,264,270,272

%N Numbers such that A231563(n)>0.

%t S[n_] := Mod[Sum[If[GCD[i, n] == 1, PowerMod[i, n, n], 0], {i, 1, n}], n]; Select[Range[1200], ! S[#] == 0 &]

%Y Cf. A231563, A231564.

%K nonn

%O 1,1

%A _José María Grau Ribas_, Dec 09 2013