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A100695
Largest denominator used in the Egyptian fraction representation of n/(n + 1) by the greedy algorithm.
5
2, 6, 4, 20, 3, 42, 24, 18, 15, 231, 12, 156, 231, 10, 240, 32640, 9, 342, 180, 126, 99, 34362, 8, 600, 312, 216, 168, 24360, 120, 633759288, 96, 88, 16728, 9240, 72, 6808, 5016, 6552, 60, 28536, 7, 1806, 924, 630, 483, 779730, 336, 294, 138075, 238, 79716
OFFSET
1,1
COMMENTS
a(n) = A247765(n,A100678(n)). - Reinhard Zumkeller, Sep 25 2014
LINKS
Alois P. Heinz, Table of n, a(n) for n = 1..5000 (first 100 terms from Reinhard Zumkeller)
EXAMPLE
a(16) = 32640 because 16/17 = 1/2 + 1/3 + 1/10 + 1/128 + 1/32640.
MATHEMATICA
a[n_] := Module[{m = n/(n+1)}, While[Numerator[m]>1, m = m-1/Ceiling[1/m]]; 1/m]; Array[a, 100] (* Jean-François Alcover, Mar 12 2019, after M. F. Hasler *)
PROG
(PARI) a(n)={n/=(n+1); while(numerator(n)>1, n-=1/ceil(1/n)); 1/n} \\ M. F. Hasler, Sep 24 2014
(Haskell)
a100695 = last . a247765_row -- Reinhard Zumkeller, Sep 25 2014
CROSSREFS
Cf. A100678.
Cf. A247765.
Sequence in context: A333923 A063427 A066092 * A275121 A174824 A009262
KEYWORD
nonn
AUTHOR
John W. Layman, Dec 08 2004
STATUS
approved