This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A136542 #5 Oct 28 2012 05:25:09
%S A136542 57,58,597,1642,5997,5998,51718,160042,556438,599997,5999998,15810772,
%T A136542 59999997,59999998,160000000042
%N A136542 Numbers n such that sigma(n)=reversal(n)+5.
%C A136542 I. If 2*10^m-1 is prime then n=3*(2*10^m-1) is in the sequence(the proof is easy).
%C A136542 II. If 3*10^m-1 is prime then n=2*(3*10^m-1) is in the sequence (the proof is easy).
%C A136542 III. If m>1 and 8*10^m+21 is prime then n=2*(8*10^m+21) is in the sequence(the proof is easy).
%C A136542 a(16) > 10^12. - _Giovanni Resta_, Oct 28 2012
%e A136542 sigma(57)=80=75+5=reversal(57)+5, so 57 is in the sequence.
%t A136542 Do[If[DivisorSigma[1,n]==FromDigits@Reverse@IntegerDigits#n+5, Print[n]],{n,160000000}]
%Y A136542 Cf. A069216.
%K A136542 base,more,nonn
%O A136542 1,1
%A A136542 _Farideh Firoozbakht_, Jan 08 2008
%E A136542 a(15) from _Giovanni Resta_, Oct 28 2012