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 A028413 #14 Aug 11 2024 14:41:29
%S A028413 0,1,2,10,18,27,100,125,173,1000,1120,1184,1355,1836,1876,1961,10000,
%T A028413 11915,100000,119084,126935,187876,188348,192383,196813,1000000,
%U A028413 1010200,1190915,1228425,1780728,1821636,1975356,10000000,11842184,12643549,12783239,18016058
%N A028413 Numbers k such that k^2 + k + 1 is a palindrome.
%H A028413 Giovanni Resta, <a href="/A028413/b028413.txt">Table of n, a(n) for n = 1..68</a>
%H A028413 P. De Geest, <a href="https://www.worldofnumbers.com/quasisq.htm">Palindromic quasi_over_squares of the form n^2+(n+1)</a>
%t A028413 palQ[n_] := Block[{d = IntegerDigits[n]}, d == Reverse[d]]; f[n_] := n^2 + n + 1; Select[Range[0, 10^5], palQ@ f@ # &] (* _Giovanni Resta_, Aug 29 2018 *)
%Y A028413 Cf. A002113, A028414, A028336, A027712.
%K A028413 nonn,base
%O A028413 1,3
%A A028413 _Patrick De Geest_
%E A028413 More terms from _Giovanni Resta_, Aug 28 2018