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A247765
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Table of denominators in the Egyptian fraction representation of n/(n+1) by the greedy algorithm.
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3
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2, 2, 6, 2, 4, 2, 4, 20, 2, 3, 2, 3, 42, 2, 3, 24, 2, 3, 18, 2, 3, 15, 2, 3, 14, 231, 2, 3, 12, 2, 3, 12, 156, 2, 3, 11, 231, 2, 3, 10, 2, 3, 10, 240, 2, 3, 10, 128, 32640, 2, 3, 9, 2, 3, 9, 342, 2, 3, 9, 180, 2, 3, 9, 126, 2, 3, 9, 99, 2, 3, 9, 83, 34362
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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. 1: 2
. 2: 2, 6
. 3: 2, 4
. 4: 2, 4, 20
. 5: 2, 3
. 6: 2, 3, 42
. 7: 2, 3, 24
. 8: 2, 3, 18
. 9: 2, 3, 15
. 10: 2, 3, 14, 231
. 11: 2, 3, 12
. 12: 2, 3, 12, 156
. 13: 2, 3, 11, 231
. 14: 2, 3, 10
. 15: 2, 3, 10, 240
. 16: 2, 3, 10, 128, 32640
. 17: 2, 3, 9
. 18: 2, 3, 9, 342
. 19: 2, 3, 9, 180
. 20: 2, 3, 9, 126
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PROG
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(Haskell)
import Data.Ratio ((%), numerator, denominator)
a247765 n k = a247765_tabf !! (n-1) !! (k-1)
a247765_tabf = map a247765_row [1..]
a247765_row n = f (map recip [2..]) (n % (n + 1)) where
f es x | numerator x == 1 = [denominator x]
| otherwise = g es
where g (u:us) | u <= x = (denominator u) : f us (x - u)
| otherwise = g us
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CROSSREFS
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KEYWORD
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nonn,tabf
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AUTHOR
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STATUS
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approved
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