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 A089182 #15 Jul 22 2020 11:41:15
%S A089182 2,22,232,2332,23532,235532,2357532,23577532,235817532,2358217532,
%T A089182 23582417532,235824417532,2358248417532,23582488417532,
%U A089182 235824908417532,2358249108417532,23582491508417532,235824915508417532
%N A089182 Prime digit palindromes 2,...,23577532 continued by adding 10^(n-k) and 10^(k-1) times prime(k).
%C A089182 Original definition: Overlapping prime-based palindromic sequence.
%C A089182 Only the first 8 terms are truly palindromes: a modulo 10 version of this would work with a limited digit set {1,2,3,5,7,9} with 2 and 5 only occurring as 1st and 3rd digit to either side.
%F A089182 a(n) = Sum_{k=1..floor(n/2)} prime(k)*(10^(n-k) + 10^(k-1)) + (n mod 2)*prime((n+1)/2)*10^floor(n/2). - _M. F. Hasler_, Apr 06 2009
%t A089182 a[m_]=Delete[Table[If [ Floor[m/2]-n>=0, Prime[ n], Prime[m-n]], {n, 1, m}], m] b=Table[Sum[a[m][[i]]*10^(i-1), {i, 1, m-1}], {m, 2, digits}]
%Y A089182 Cf. A007907, A138140.
%K A089182 nonn,base
%O A089182 1,1
%A A089182 _Roger L. Bagula_, Dec 07 2003
%E A089182 Edited by _M. F. Hasler_, Apr 06 2009