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 A230806 #8 Dec 06 2015 22:43:09
%S A230806 1878781,11782828711,13828882831,33694849633,36331813363,76093839067,
%T A230806 93121812139,1018278728101,1101228221011,1200528250021,1237788877321,
%U A230806 1296978796921,1318608068131,1449108019441,1477968697741,1608678768061,1713708073171,1792308032971
%N A230806 The smallest of 4 consecutive palindromic numbers that are all primes.
%C A230806 There cannot be 5 consecutive palindromic numbers that are all primes. The central digit of all numbers in the sequence will be 8.
%H A230806 Shyam Sunder Gupta, <a href="/A230806/b230806.txt">Table of n, a(n) for n = 1..2166</a>
%e A230806 1878781 is in the sequence because 1878781, 1879781, 1880881 and 1881881 are consecutive palindromic numbers that are all primes.
%t A230806 a = {}; m = 0; Do[z = n*10^(IntegerLength[n] - 1) + FromDigits@Rest@Reverse@IntegerDigits[n]; If[PrimeQ[z], m = m + 1; If[m == 1, z1 = z]; If[m == 4, AppendTo[a, z1]], m = 0], {n, 1, 1000000000}]
%Y A230806 Cf. A000040, A002113, A002385, A032595.
%K A230806 nonn,base
%O A230806 1,1
%A A230806 _Shyam Sunder Gupta_, Oct 30 2013