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 A305396 #6 Jun 25 2018 14:02:33 %S A305396 101,110,211,220,321,330,431,440,541,550 %N A305396 Records in A171797. %C A305396 The record-holders are the powers of 2 written in base 4, A004643. %D A305396 M. E. Coppenbarger, Iterations of a modified Sisyphus function, Fib. Q., 56 (No. 2, 2018), 130-141. %Y A305396 Cf. A171797, A004643. %K A305396 nonn,base,more %O A305396 1,1 %A A305396 _N. J. A. Sloane_, Jun 25 2018