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 A260459 #10 Oct 02 2015 13:05:52
%S A260459 30103,333010333,33330103333,9333301033339,12933330103333921,
%T A260459 121293333010333392121,3812129333301033339212183,
%U A260459 15381212933330103333921218351,101538121293333010333392121835101,3910153812129333301033339212183510193
%N A260459 Minimal nested palindromic primes with seed 010.
%C A260459 Let s be a palindrome and put a(1) = s. Let a(2) be the least palindromic prime having s in the middle; for n > 2, let a(n) be the least palindromic prime having a(n-1) in the middle. Then (a(n)) is the sequence of minimal nested palindromic primes with seed s. (For A260459, the seed is not an integer, so that the offset is 2.)
%e A260459 As a triangle:
%e A260459 010
%e A260459 30103
%e A260459 333010333
%e A260459 33330103333
%e A260459 9333301033339
%e A260459 12933330103333921
%e A260459 121293333010333392121
%e A260459 3812129333301033339212183
%t A260459 s0 = "010"; s = {ToExpression[s0]};Do[NestWhile[# + 1 &, 1, ! PrimeQ[tmp = FromDigits[Join[#, IntegerDigits[Last[s], 10, Max[StringLength[s0],Length[IntegerDigits[Last[s]]]]], Reverse[#]]&[IntegerDigits[#]]]] &]; AppendTo[s, tmp], {10}]; s0 <> ", " <> StringTake[ToString[Rest[s]], {2, -2}]
%t A260459 (* _Peter J. C. Moses_, Sep 23 2015 *)
%Y A260459 Cf. A261881.
%K A260459 nonn,base,easy
%O A260459 2,1
%A A260459 _Clark Kimberling_, Sep 24 2015