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 A070831 #6 Nov 06 2015 02:02:05
%S A070831 191,353,13331,1123211,1221221,1303031,1311131,3103013,110232011,
%T A070831 111050111,112030211,112111211,121111121,130030031,301111103,
%U A070831 10000900001,10002520001,10013131001,10111311101,10301110301
%N A070831 Palindromic primes with digit sum = 11.
%C A070831 Conjecture: The sequence is unbounded.
%H A070831 Chai Wah Wu, <a href="/A070831/b070831.txt">Table of n, a(n) for n = 1..2388</a>
%t A070831 Do[p = Join[ IntegerDigits[n], Reverse[ Drop[ IntegerDigits[n], -1]]]; q = Plus @@ p; If[ PrimeQ[ FromDigits[p]] && q == 11, Print[ FromDigits[p]]], {n, 1, 10^6}]
%Y A070831 Cf. A002385, A070247, A070248 and A070249.
%K A070831 base,nonn
%O A070831 1,1
%A A070831 _Robert G. Wilson v_, May 15 2002