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 A084123 #14 Mar 12 2015 19:00:30
%S A084123 2,6,55,444,848,122555221,161131161,5729689869275,7587952597857,
%T A084123 35757255275753,182196497222794691281
%N A084123 Palindromic numbers which are equal to a number n multiplied by the n-th prime.
%C A084123 a(12) > 4.3*10^26. [_Giovanni Resta_, Jun 28 2013]
%e A084123 The palindrome 161131161 is in the sequence since 39119 is the 4119th prime and 4199*39119 = 161131161.
%t A084123 palQ[n_]:=FromDigits[Reverse[IntegerDigits[n]]]==n; t={}; Do[If[palQ[x=n*Prime[n]],AppendTo[t,x]],{n,15*10^5}]; t (* _Jayanta Basu_, May 11 2013 *)
%Y A084123 Cf. A084121, A084122.
%K A084123 base,nonn
%O A084123 1,1
%A A084123 _Giovanni Resta_, May 14 2003