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 A119163 #13 May 18 2025 19:59:17
%S A119163 7,312,1287,1297912,7054712,7521287,2384302087
%N A119163 Numbers k such that the k-th triangular number contains only digits {2,4,8}.
%C A119163 Next term exceeds 1.4*10^20. - _Max Alekseyev_, May 18 2025
%H A119163 Giovanni Resta, <a href="http://www.numbersaplenty.com/tr/tr248.html">Tridigital Triangular Numbers</a>
%Y A119163 Cf. A000217, A119162. See A119034 for a table of cross-references.
%K A119163 nonn,base,more
%O A119163 1,1
%A A119163 _Giovanni Resta_, May 10 2006