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 A119090 #13 Mar 30 2023 20:56:13
%S A119090 3,11,36,363,1095,1271283,3687839,34642771,3705851211,133181080239,
%T A119090 365754039996,127034546483126864,1333271810847736239,
%U A119090 4001669872957554920
%N A119090 Numbers k such that the k-th triangular number contains only digits {0,6,8}.
%H A119090 Giovanni Resta, <a href="http://www.numbersaplenty.com/tr/tr068.html">Tridigital Triangular Numbers</a>
%Y A119090 Cf. A000217, A119089. See A119034 for a table of cross-references.
%K A119090 nonn,base,more
%O A119090 1,1
%A A119090 _Giovanni Resta_, May 10 2006
%E A119090 a(12)-a(14) from _Tyler Busby_, Mar 30 2023