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 A230005 #28 Feb 11 2014 01:15:56
%S A230005 489,4629,296206,460029,29589106,46000029,2927272726,4045046518,
%T A230005 21223345084,29600331295,296151515206,460000000029
%N A230005 Numbers n such that phi(n) + sigma(n) = reversal(n) - 4.
%C A230005 If p = 15*10^k+10+(10^k-1)/3 is prime then 3*p is in the sequence.
%C A230005 a(7) is greater than 1.3*10^8.
%C A230005 a(11) > 10^11. - _Donovan Johnson_, Nov 08 2013
%C A230005 If p=(1/11)*(23*100^m-1) is prime then 14*p is a term of the sequence. - _Farideh Firoozbakht_, Nov 08 2013
%C A230005 a(13) > 10^13. - _Giovanni Resta_, Feb 08 2014
%C A230005 If p = (1685*10^(2k+2)+31)/33 is prime then 58*p is in the sequence. For k = 0, 3, 9, 30, 42, 51, 120, 846, ... p is prime. - _Farideh Firoozbakht_, Feb 10 2014
%e A230005 489 is in the sequence because phi(489)+sigma(489) = 324+656 = 984-4 = reversal(489)-4.
%t A230005 Do[If[FromDigits@Reverse@IntegerDigits@n-4 == EulerPhi[n] + DivisorSigma[1, n], Print[n]], {n, 130000000}]
%o A230005 (PARI) is(n)=subst(Polrev(digits(n)),'x,10)-4==eulerphi(n)+sigma(n) \\ _Charles R Greathouse IV_, Nov 08 2013
%Y A230005 Cf. A000010, A000203, A004086, A070272, A230004, A230006, A230019, A136544, A237521, A237522.
%K A230005 nonn,base,more
%O A230005 1,1
%A A230005 _Farideh Firoozbakht_, Nov 07 2013
%E A230005 a(7)-a(10) from _Donovan Johnson_, Nov 08 2013
%E A230005 a(11)-a(12) from _Giovanni Resta_, Feb 06 2014