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%I #14 Sep 08 2018 04:27:04
%S 572,592,5992,599992,2014080,5999992,594637872,599999992,599999999992
%N Numbers n such that phi(reversal(n)) + sigma(reversal(n)) = n.
%C If n is in the sequence A070272 then reversal(n) is in this sequence. 10 divides all other terms of the sequence. 2014080 is the only known such term.
%C If p=6*10^n-1 is a prime greater than 5 then reversal(5*p) is in the sequence, see comment lines of A070272.
%C There is no further term up to 10^9.
%C 10^12 < a(10) <= 1442827967760. - _Giovanni Resta_, Sep 04 2018
%e 2014080 = phi(804102) + sigma(804102), so 2014080 is in the sequence.
%t r[n_]:=FromDigits[Reverse[IntegerDigits[n]]];
%t Do[If[EulerPhi[r[n]]+DivisorSigma[1,r[n]]==n,Print[n]],{n,1000000000}]
%Y Cf. A000010, A000203, A004086, A070272, A178324, A178325.
%K nonn,base,more
%O 1,1
%A _Farideh Firoozbakht_, May 28 2010
%E a(9) from _Giovanni Resta_, Sep 04 2018
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