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 A070835 #9 Feb 11 2014 19:05:28 %S A070835 1,168,1141,1451,2139,2737,3938,7597,11831,19668,21415,23649,31894, %T A070835 32383,40649,52687,59677,121023,133661,136831,146055,148503,172095, %U A070835 190035,245998,276058,302005,302503,307705,396635,410389,504557,516439,539327,571577 %N A070835 Numbers n such that phi(reverse(n)) = sigma(n). %H A070835 Donovan Johnson, <a href="/A070835/b070835.txt">Table of n, a(n) for n = 1..500</a> %e A070835 phi(reverse(168)) = phi(861) = 480 = sigma(168), so 168 is a term of the sequence. %t A070835 Select[Range[10^5], EulerPhi[FromDigits[Reverse[IntegerDigits[ # ]]]] == DivisorSigma[1, # ] &] %Y A070835 Cf. A000203, A000010, A004086, A070856. %K A070835 base,nonn %O A070835 1,2 %A A070835 _Joseph L. Pe_, May 16 2002 %E A070835 More terms from _Labos Elemer_, Jul 04 2003