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Smallest x such that x-1 mod phi(x) = n, or 0 if no such x exists.
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%I #8 Feb 27 2016 11:13:46

%S 1,4,9,8,25,18,15,16,21,50,35,36,33,98,39,32,65,54,51,100,45,70,95,72,

%T 69,338,63,196,161,110,87,64,93,130,75,108,217,182,99,200,185,170,123,

%U 140,117,190,215,144,141,250,235

%N Smallest x such that x-1 mod phi(x) = n, or 0 if no such x exists.

%C Conjecture: a(n) > 0 for all n.

%o (PARI) a(n) = {my(x = 1); while ((x-1) % eulerphi(x) != n, x++); x;} \\ _Michel Marcus_, Feb 27 2016

%Y Cf. A215486.

%K nonn

%O 0,2

%A _Christina Steffan_, Feb 08 2016