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 A007734 #21 Feb 13 2014 13:17:12 %S A007734 1,1,1,2,4,1,6,2,1,4,5,2,3,6,4,4,16,1,18,4,6,5,11,2,20,3,1,6,28,4,30, %T A007734 8,5,16,12,2,18,18,3,4,8,6,42,10,4,11,23,4,42,20,16,6,52,1,20,6,18,28, %U A007734 29,4,10,30,6,16,12,5,22,16,11,12,35,2,12,18,20,18,30,3,78,4,1,8,41,6,16,42 %N A007734 Period of repeating digits of 1/n in base 3. %H A007734 T. D. Noe, <a href="/A007734/b007734.txt">Table of n, a(n) for n=1..1000</a> %H A007734 <a href="/index/1#1overn">Index entries for sequences related to decimal expansion of 1/n</a> %t A007734 f[n_] := MultiplicativeOrder[3, n/(3^IntegerExponent[n, 3])]; Array[f, 80] (* _Robert G. Wilson v_, Jun 10 2011 *) %o A007734 (PARI) a(n)=znorder(Mod(3,n/3^valuation(n,3))) \\ _Charles R Greathouse IV_, Jun 10 2011 %K A007734 nonn,base %O A007734 1,4 %A A007734 _N. J. A. Sloane_, Hal Sampson (hals(AT)easynet.com) %E A007734 More terms from _David W. Wilson_