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 A028414 #13 Aug 11 2024 14:41:29
%S A028414 1,3,7,111,343,757,10101,15751,30103,1001001,1255521,1403041,1837381,
%T A028414 3372733,3521253,3847483,100010001,141979141,10000100001,14181118141,
%U A028414 16112621161,35297579253,35475157453,37011411073,38735553783,1000001000001,1020505050201
%N A028414 Palindromes of form k^2 + k + 1.
%H A028414 Giovanni Resta, <a href="/A028414/b028414.txt">Table of n, a(n) for n = 1..68</a>
%H A028414 P. De Geest, <a href="https://www.worldofnumbers.com/quasisq.htm">Palindromic quasi_over_squares of the form n^2+(n+1)</a>
%t A028414 palQ[n_] := Block[{d = IntegerDigits[n]}, d == Reverse[d]]; f[n_] := n^2 + n + 1; Select[f@ Range[0, 10^5], palQ] (* _Giovanni Resta_, Aug 29 2018 *)
%Y A028414 Cf. A028413, A028337, A027713.
%K A028414 nonn,base
%O A028414 1,2
%A A028414 _Patrick De Geest_
%E A028414 More terms from _Giovanni Resta_, Aug 28 2018