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%I #14 Feb 11 2014 19:05:28
%S 1,65,2771,10920,158804,2413091,16636354,117650080,140766297,
%T 630947067,4639526938,153896850898
%N Numbers n such that phi(n) is the reversal of sigma(n).
%C a(13) > 10^12. - _Giovanni Resta_, Nov 03 2012
%e phi(65) = 48 = reversal(84) = reversal(sigma(65)), so 65 belongs to the sequence.
%e n=2413091, sigma[n]=2528032, phi[n]=2308152=rev[sigma[n]].
%t Select[Range[10^6], EulerPhi[ # ] == FromDigits[Reverse[IntegerDigits[DivisorSigma[1, # ]]]] &]
%Y Cf. A000010, A000203, A004086.
%K base,nonn
%O 1,2
%A _Joseph L. Pe_, Apr 12 2002
%E a(6)-a(8) from _Labos Elemer_, Oct 22 2004
%E a(9)-a(11) from _Donovan Johnson_, Jan 14 2011
%E a(12) from _Giovanni Resta_, Nov 03 2012
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