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%I #10 Aug 08 2012 12:41:51
%S 52416,435456,1713600,6407424,9067520,62000640,535392000,46367354880
%N Numbers n such that if sum of the proper divisors of n is equal to m then n = phi(m).
%C Next term is greater than 65*10^6.
%C 241287413760 and 6094936793088000 are also terms - _Donovan Johnson_, Aug 08 2012
%e 62000640 is in the sequence because sigma(62000640)-62000640 = 187545888 and phi(187545888) = 62000640.
%t Do[If[n == EulerPhi[DivisorSigma[1, n]-n], Print[n]], {n, 65000000}]
%Y Cf. A107653.
%K more,nonn
%O 1,1
%A _Farideh Firoozbakht_, May 26 2005
%E a(7) from _Donovan Johnson_, Oct 12 2008
%E a(8) from _Donovan Johnson_, Aug 08 2012
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