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A154887 Number of ways to partition n into distinct reduced fractions i/j with j<=n. 3
1, 2, 11, 71, 838, 7915, 181443 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..7.

EXAMPLE

a(3) = #{3, 8/3+1/3, 5/2+1/2, 7/3+2/3, 2+1, 2+2/3+1/3, 5/3+4/3, 5/3+1+1/3, 3/2+1+1/2, 3/2+2/3+1/2+1/3, 4/3+1+2/3} = 11.

CROSSREFS

A154886, A154888, A143270.

Sequence in context: A214692 A186633 A291301 * A323842 A049671 A074609

Adjacent sequences:  A154884 A154885 A154886 * A154888 A154889 A154890

KEYWORD

more,nonn

AUTHOR

Reinhard Zumkeller, Jan 17 2009

EXTENSIONS

Example corrected by Reinhard Zumkeller, Feb 02 2009

STATUS

approved

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Last modified October 23 07:11 EDT 2019. Contains 328336 sequences. (Running on oeis4.)