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 A101316 #9 May 19 2021 00:21:19 %S A101316 1,2,21,32,33,34,41,51,62,63,71,82,84,91,93,211,311,411,511,522,531, %T A101316 533,622,711,713,721,731,733,742,751,753,754,822,911,913,915,2111, %U A101316 3111,3122,4112 %N A101316 Sequence starts with 1 odd digit, 2 even digits, 2 odd digits, 1 even digit, then 3 odd, 2 even, 3 odd, 3 even, 3 odd, 4 even, 4 odd, 1 even, etc., where these digits are determined by the sequence itself, and the parity alternates. Always group the digits to give the slowest rate of growth subject to a(n-1) < a(n). %C A101316 Self-description of the size of the blocks of similar-parity digits with a(n) < a(n+1). %K A101316 base,nonn,more %O A101316 1,2 %A A101316 _Eric Angelini_, Jan 25 2005