A047195 - OEIS

The OEIS is supported by the many generous donors to the OEIS Foundation.

A047195

Number of nonempty subsets of {1,2,...,n} in which exactly 2/3 of the elements are <= n/3.

0

0, 0, 0, 0, 0, 4, 5, 6, 18, 21, 24, 76, 90, 105, 325, 385, 450, 1390, 1651, 1939, 6027, 7175, 8456, 26348, 31416, 37122, 116010, 138510, 164025, 513729, 614019, 728409, 2285569, 2734171, 3248322, 10208110, 12220780, 14536951

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,6

LINKS

Table of n, a(n) for n=1..38.

CROSSREFS

Sequence in context: A235711 A010753 A221174 * A109889 A103518 A103313

Adjacent sequences: A047192 A047193 A047194 * A047196 A047197 A047198

KEYWORD

nonn

AUTHOR

Clark Kimberling

STATUS

approved