%I
%S 0,1,2,1,4,4,6,1,8,9,10,9,12,11,14,1,16,10,18,16,20,20,22,16,24,25,26,
%T 25,28,25,30,1,32,33,34,28,36,36,38,25,40,36,42,37,44,41,46,33,48,49,
%U 50,48,52,28,54,49,56,57,58,45,60,59,62,1,64,64,66,64,68
%N Greatest residue of x^n (mod n), x=0..n1.
%C a(n) = 1 if n is of the form 2^p and a(n) = n1 if n prime.
%e a(18) = 10 because x^18 == 0, 1, 9, 10 (mod 18) => 10 is the greatest residue.
%t Table[Max[Union[PowerMod[Range[0, n  1], n, n]]], {n, 100}]
%Y Cf. A072994, A195637.
%K nonn
%O 1,3
%A _Michel Lagneau_, Sep 27 2011
