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A047189 Number of nonempty subsets of {1,2,...,n} in which exactly 3/5 of the elements are <= (n-2)/2. 0
0, 0, 0, 0, 0, 0, 0, 10, 15, 60, 84, 210, 280, 630, 846, 2142, 3045, 8400, 12320, 32802, 48048, 121110, 176670, 437580, 642642, 1608607, 2391895, 6034600, 9050470, 22712326, 34185606, 84996158, 128251383, 317302008 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,8

LINKS

Table of n, a(n) for n=1..34.

CROSSREFS

Sequence in context: A272307 A092192 A119039 * A278921 A035407 A020139

Adjacent sequences:  A047186 A047187 A047188 * A047190 A047191 A047192

KEYWORD

nonn

AUTHOR

Clark Kimberling

STATUS

approved

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Last modified September 17 17:29 EDT 2021. Contains 347489 sequences. (Running on oeis4.)