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%I #7 Mar 15 2014 17:57:23
%S 1259196,1473381
%N Numbers n such that sigma(n) = reversal(2n).
%C a(3) > 10^12. - _Giovanni Resta_, Mar 15 2014
%t rev[n_] := FromDigits@ Reverse@ IntegerDigits@n; Select[Range[2*10^6], DivisorSigma[1, #] == rev[2*#] &] (* _Giovanni Resta_, Mar 15 2014 *)
%Y Cf. A000203, A004086, A233467.
%K nonn,base,more,bref
%O 1,1
%A _Farideh Firoozbakht_, Mar 14 2014
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