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%I #9 Feb 04 2016 16:15:37
%S 3,5,7,9,11,15,33,45,385
%N The fifth of the five known sets of nine distinct odd numbers the sum of whose reciprocals is 1.
%C John Leech showed that nine is the smallest number of odd numbers with this property.
%C This set was apparently discovered by S. Yamashita in 1976.
%D R. K. Guy, Unsolved Problems in Number Theory (UPINT), Section D11.
%H 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 The Prime Puzzles and Problems Connection, <a href="http://www.primepuzzles.net/problems/prob_035.htm">Problem 35</a>
%H <a href="/index/Ed#Egypt">Index entries for sequences related to Egyptian fractions</a>
%Y There are five known sets of nine odd numbers with this property: A201644, A201646, A201647, A201648, A201649.
%K nonn,fini,full
%O 1,1
%A _N. J. A. Sloane_, Dec 03 2011