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 A119153 #12 Mar 31 2023 02:28:21
%S A119153 2,10,22,25,102,714,2114,2170,2550,21097,671302,258973177,1023088777,
%T A119153 22460425354,211297574645,668630474213122229
%N A119153 Numbers k such that the k-th triangular number contains only digits {2,3,5}.
%H A119153 Giovanni Resta, <a href="http://www.numbersaplenty.com/tr/tr235.html">Tridigital Triangular Numbers</a>.
%Y A119153 Cf. A000217, A119152. See A119034 for a table of cross-references.
%K A119153 nonn,base,more
%O A119153 1,1
%A A119153 _Giovanni Resta_, May 10 2006
%E A119153 a(16) from _Tyler Busby_, Mar 31 2023