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 A119095 #10 Apr 06 2023 20:03:13
%S A119095 990,809809890,89909089088809980,98899080989088808000999800
%N A119095 Triangular numbers composed of digits {0,8,9}.
%C A119095 a(5) > 10^41. - _Tyler Busby_, Mar 28 2023
%H A119095 Giovanni Resta, <a href="http://www.numbersaplenty.com/tr/tr089.html">Tridigital Triangular Numbers</a>.
%F A119095 a(n) = A000217(A119096(n)). - _Tyler Busby_, Mar 28 2023
%Y A119095 Cf. A000217, A058456, A119096. See A119033 for a table of cross-references.
%K A119095 nonn,base,more
%O A119095 1,1
%A A119095 _Giovanni Resta_, May 10 2006