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%I #15 Mar 05 2014 10:39:17
%S 132496,1052576,5656464,12936992,19230208,187545888,1740340368,
%T 163150299648
%N Numbers n such that n = sigma(phi(n)) - phi(n).
%C A107654(n) = phi(A238233(n)).
%C Other terms are 748001267712 and 21301524386075232 (see comment in A107654).
%p with(numtheory); list_A238233:=proc(q) local n;
%p for n from 1 to q do if n=sigma(phi(n))-phi(n) then print(n);
%p fi; od; end: list_A238233(10^9);
%Y Cf. A000010, A000203, A107654.
%K nonn,more
%O 1,1
%A _Paolo P. Lava_, Feb 25 2014