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A048041 Number of nonempty subsets of {1,2,...,n} in which exactly 1/4 of the elements are <= (n+1)/3. 0
0, 0, 0, 1, 2, 8, 20, 30, 63, 126, 182, 392, 844, 1270, 2800, 5995, 9020, 19595, 41951, 63518, 138866, 299411, 455966, 997640, 2154104, 3290520, 7201692, 15584085, 23878212, 52311408, 113406028, 174179258, 381766253, 828748052 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

LINKS

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

CROSSREFS

Sequence in context: A162626 A137306 A110856 * A217513 A071386 A031114

Adjacent sequences:  A048038 A048039 A048040 * A048042 A048043 A048044

KEYWORD

nonn

AUTHOR

Clark Kimberling

STATUS

approved

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Last modified December 9 17:46 EST 2016. Contains 278985 sequences.