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%I #11 Feb 08 2014 16:04:47
%S 1,37,225,397,11112722,1309286244182
%N Numbers n such that sigma(n) + phi(n) = reversal(n) + 1.
%C If p=4*10^m-3 is prime then p is in the sequence.
%C a(7) > 10^13. - _Giovanni Resta_, Feb 08 2014
%e sigma(37)+phi(37)=38+36=73+1=reversal(37)+1.
%t r[n_] := FromDigits[Reverse[IntegerDigits[n]]]; Do[If[DivisorSigma[1, n] + EulerPhi[n] == r[n]+1, Print[n]], {n, 1000000000}]
%Y Cf. A000010, A000203, A004086, A230004, A230005.
%K nonn,base,more
%O 1,2
%A _Farideh Firoozbakht_, Dec 02 2013
%E a(6) from _Giovanni Resta_, Feb 06 2014
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