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%I #10 Dec 14 2013 02:06:17
%S 1,611379,614077809,61199999379,611999999379
%N Numbers n such that sigma(n) = reversal(n+9).
%C If p=68*10^m-69 is prime then 9*p is in the sequence.
%C 611379 and 61199999379 are such terms of the sequence.
%C a(6) > 6.4*10^12. - _Giovanni Resta_, Dec 13 2013
%e sigma(1)=1=reversal(10)=reversal(1+9),
%e sigma(611379)=883116=reversal(611388)=reversal(611379+9).
%t Select[Range[700000], DivisorSigma[1,#] == FromDigits[Reverse[IntegerDigits[#+9]]]&]
%Y Cf. A000203, A004086, A230021.
%K nonn,base,more
%O 1,2
%A _Farideh Firoozbakht_, Dec 06 2013
%E a(3)-a(5) from _Giovanni Resta_, Dec 13 2013