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A201644
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The first of the five known sets of nine distinct odd numbers the sum of whose reciprocals is 1.
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27
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OFFSET
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1,1
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COMMENTS
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John Leech showed that nine is the smallest number of odd numbers with this property.
This set was apparently discovered by S. Yamashita in 1976.
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REFERENCES
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R. K. Guy, Unsolved Problems in Number Theory (UPINT), Section D11.
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LINKS
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Table of n, a(n) for n=1..9.
The Prime Puzzles and Problems Connection, Problem 35
Index entries for sequences related to Egyptian fractions
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EXAMPLE
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1/3+1/5+1/7+1/9+1/11+1/15+1/35+1/45+1/231 = 1
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CROSSREFS
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There are five known sets of nine odd numbers with this property: A201644, A201646, A201647, A201648, A201649.
Sequence in context: A133848 A220077 A201649 * A064076 A050842 A143447
Adjacent sequences: A201641 A201642 A201643 * A201645 A201646 A201647
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KEYWORD
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nonn,fini,full
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AUTHOR
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N. J. A. Sloane, Dec 03 2011
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STATUS
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approved
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