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 A201644 #21 Feb 04 2016 12:25:19 %S A201644 3,5,7,9,11,15,35,45,231 %N A201644 The first of the five known sets of nine distinct odd numbers the sum of whose reciprocals is 1. %C A201644 John Leech showed that nine is the smallest number of odd numbers with this property. %C A201644 This set was apparently discovered by S. Yamashita in 1976. %D A201644 R. K. Guy, Unsolved Problems in Number Theory (UPINT), Section D11. %H A201644 Nechemia Burshtein, <a href="http://dx.doi.org/10.1016/j.jnt.2007.01.007">The equation sum(i=1,9,1/xi)=1 in distinct odd integers has only the five known solutions</a>, Journal of Number Theory, Volume 127, Issue 1, November 2007, Pages 136-144. %H A201644 The Prime Puzzles and Problems Connection, <a href="http://www.primepuzzles.net/problems/prob_035.htm">Problem 35</a> %H A201644 <a href="/index/Ed#Egypt">Index entries for sequences related to Egyptian fractions</a> %e A201644 1/3+1/5+1/7+1/9+1/11+1/15+1/35+1/45+1/231 = 1. %Y A201644 There are five known sets of nine odd numbers with this property: A201644, A201646, A201647, A201648, A201649. %K A201644 nonn,fini,full %O A201644 1,1 %A A201644 _N. J. A. Sloane_, Dec 03 2011