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 A065147 #8 Oct 09 2013 14:16:57 %S A065147 72,79,84,91,100,121,144,202,244,400,1210,10201,1100100, %T A065147 1111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111 %N A065147 100 written in base 15-n. %C A065147 The term 111....1111 should officially be called the "unary expansion", since in base 1 only the digit 0 may appear. %Y A065147 Cf. A065004. %K A065147 base,less,fini,full,nonn %O A065147 1,1 %A A065147 _Bodo Zinser_, Nov 19 2001