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 A066338 #12 Feb 03 2020 15:23:22 %S A066338 0,1,2,3,4,8,9,10,11,12,13,14,15,-1,-1,-1,16,17,18,19,20,24,25,26,27, %T A066338 28,29,30,31,-1,-1,-1,32,33,34,35,36,40,41,42,43,44,45,46,47,-1,-1,-1, %U A066338 48,49,50,51,52,56,57,58,59,60,61,62,63,-1,-1,-1,64,65,66,67,68,72,73,74,75,76,77,78,79,-1,-1,-1,80,81,82,83,84,88,89 %N A066338 Decimal equivalent of A066330. %K A066338 sign,base %O A066338 0,3 %A A066338 _George E. Antoniou_, Dec 15 2001 %E A066338 Corrected by _Sascha Kurz_, Feb 02 2003 %E A066338 More terms from _Joshua Zucker_, Jun 21 2006