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%I #6 Oct 28 2012 13:23:55
%S 7142167,75018277,71859221859
%N Numbers n such that sigma(n)=reversal(n)-1.
%C a(4) > 10^12. - _Giovanni Resta_, Oct 28 2012
%e sigma(75018277)=77281056=77281057-1=reversal(75018277)-1, so 75018277 is in the sequence.
%t Do[If[DivisorSigma[1,n]==FromDigits@Reverse@IntegerDigits@n-1,Print[n]], {n,1553000000}]
%Y Cf. A137598.
%K base,more,nonn,bref
%O 1,1
%A _Farideh Firoozbakht_, Feb 23 2008
%E a(3) from _Giovanni Resta_, Oct 28 2012
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