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 A084121 #16 Jul 16 2020 17:41:05
%S A084121 2,3,11,37,53,33827,39119,9260479,10708871,23858227,65941772591
%N A084121 Primes p_n such that n*p_n is a palindrome.
%C A084121 a(12) > 10^14. [_Giovanni Resta_, Jun 28 2013]
%e A084121 The 4119th prime 39119 is in the sequence since 4199*39119 = 161131161 is a palindrome.
%t A084121 palQ[n_]:=FromDigits[Reverse[IntegerDigits[n]]]==n; t={}; Do[p=Prime[n]; If[palQ[p*n],AppendTo[t,p]],{n,15*10^5}]; t (* _Jayanta Basu_, May 11 2013 *)
%t A084121 Module[{nn=2763*10^6},Select[Thread[{Range[nn],Prime[Range[nn]]}],PalindromeQ[ Times@@ #]&]][[All,2]] (* Requires Mathematica version 10 or later *) (* The program will take a long time to run. *) (* _Harvey P. Dale_, Jul 16 2020 *)
%Y A084121 Cf. A084122, A084123.
%K A084121 base,nonn
%O A084121 1,1
%A A084121 _Giovanni Resta_, May 14 2003