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 A259085 #14 Jun 19 2015 16:33:33 %S A259085 91,43,42,30,-1,14,13,23,7,3,-1,6,-1,3,5,2,19,-1,9,-1,17,5,6,9,6,-1, %T A259085 -1,-1,11,-1,13,-1,7,-1,5,-1,5,3,13,6,7,-1,-1,7,10,15,-1,2,5,7,2,9,-1, %U A259085 -1,2,6,1,-1,2,-1,21,2,3,-1,3,11,-1,5,11,3,3,3,5,1 %N A259085 a(n) = largest k such that the decimal representation of prime(n)^k does not contain the digit 1, or -1 if no such k exists. %C A259085 These values are only conjectural. %H A259085 Hiroaki Yamanouchi, <a href="/A259085/b259085.txt">Table of n, a(n) for n = 1..500</a> %H A259085 Popular Computing (Calabasas, CA), <a href="/A094776/a094776.jpg">Two Tables</a>, Vol. 1, (No. 9, Dec 1973), page PC9-16. %Y A259085 Cf. A094776, A259081-A259086. %K A259085 sign,base %O A259085 1,1 %A A259085 _N. J. A. Sloane_, Jun 18 2015 %E A259085 a(14)-a(74) from _Hiroaki Yamanouchi_, Jun 19 2015