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%I #16 Aug 01 2019 03:50:01
%S 1,1,2,2,2,2,2,4,2,2,2,2,2,10,6,2,2,2,2,8,2,2,2,12,2,22,2,2,15,2,2,4,
%T 28,2,12,36,2,2,2,2,2,2,44,48,20,2,2,18,2,2,46,6,28,2,2,2,52,22,2,2,2,
%U 58,2,2,18,80,2,2,2,2,45,2,70,28,6,48,2,2,2
%N Multiplicative order of phi(n) modulo n when gcd(phi(n),n)=1.
%H Giovanni Resta, <a href="/A239202/b239202.txt">Table of n, a(n) for n = 1..10000</a>
%e For n = 8: the 8th entry of A003277 is 15, and phi(15) = 8 has multiplicative order 4 modulo 15, so a(8) = 4.
%t MultiplicativeOrder[EulerPhi[#], #] & /@ Select[Range[1000], GCD[#, EulerPhi[#]] == 1 &]
%o (PARI) lista(nn) = {for(n=1, nn, my(ephi = eulerphi(n)); if (gcd(ephi, n) == 1, print1(znorder(Mod(ephi, n)), ", ")););} \\ _Michel Marcus_, Feb 09 2015
%Y Indexed by A003277.
%K nonn
%O 1,3
%A _Alexander Gruber_, Mar 12 2014