%I #4 Apr 15 2020 00:12:57
%S 1,2,1,4,6,4,2,8,4,6,14,4,22,2,16,16,21,4,25,16,4,14,26,16,19,22,13,4,
%T 16,16,33,32,82,50,36,4,84,62,22,16,18,4,16,100,49,26,122,16,65,46,52,
%U 68,7,40,26,88,25,16,19,16,3,66,4,64,66,82,127,52,94,36
%N a(n) is the smallest positive number k such that n divides 4^k - k.
%F a(4^m) = 4^m for m >= 0.
%o (PARI) a(n) = for(k=1, oo, if(Mod(4, n)^k==k, return(k)));
%Y Cf. A072872, A333335, A333339, A333341.
%K nonn
%O 1,2
%A _Jinyuan Wang_, Apr 14 2020
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