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 A091331 #9 Jan 20 2019 23:18:40
%S A091331 123,456,789,101,112,131,415,161,718,192,21,222,324,252,627,282,930,
%T A091331 313,233,343,536,373,839,404,142,434,445,464,748,495,51,525,354,555,
%U A091331 657,585,960,616,263,646,566,676,869,707,172,737,475,767,778,798,81,828,384
%N A091331 Natural numbers written out with their digits grouped in triples (leading zeros omitted).
%H A091331 Rémy Sigrist, <a href="/A091331/b091331.txt">Table of n, a(n) for n = 1..10000</a>
%t A091331 FromDigits/@Partition[Flatten[IntegerDigits/@Range[90]],3] (* _Harvey P. Dale_, Jun 25 2013 *)
%o A091331 (PARI) {c=0;d=[];for(n=1,99,while(#d<3,d=concat(d,digits(c++))); print1(d[1]*100+d[2]*10+d[3]",");d=vecextract(d,"^..3"))} \\ _M. F. Hasler_, Oct 23 2014
%Y A091331 Cf. A059805, A091332.
%K A091331 base,easy,nonn
%O A091331 1,1
%A A091331 J. Taylor (integersfan(AT)yahoo.com), Mar 01 2004