%I #7 Feb 11 2014 19:05:30
%S 1,3,5,11,23,55,87,123,383,501,957,1015,3565,3777,5667,6141,9069,
%T 11033,13827,27347,35119,44693,55645,91915,137037,156919,180251,
%U 233935,261989,269395,294679,315605,335995,361645,380103,389809,410201,428399,443267
%N Numbers n such that phi(n + phi(n)) = sigma(n).
%H Donovan Johnson, <a href="/A074874/b074874.txt">Table of n, a(n) for n = 1..500</a>
%e sigma(23) = 24 = phi(23 + 22) = phi(23 + phi(23)), so 23 is a term of the sequence.
%e phi(87 + phi(87)) = phi(87 + 56) = 120 = sigma(87), so 87 is a member of the sequence.
%t Select[Range[10^5], EulerPhi[ # + EulerPhi[ # ]] == DivisorSigma[1, # ] &]
%K nonn
%O 1,2
%A _Joseph L. Pe_, Sep 12 2002
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