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A048013
Number of nonempty subsets of {1,2,...,n} in which exactly 4/5 of the elements are <= (n-1)/3.
0
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 9, 10, 11, 55, 60, 65, 195, 210, 225, 525, 560, 595, 1326, 1413, 1501, 3933, 4230, 4536, 13860, 15015, 16215, 49335, 53460, 57750, 163175, 176345, 190035, 509067, 549094, 590759, 1580761, 1705795
OFFSET
1,13
CROSSREFS
Sequence in context: A054967 A227801 A048031 * A048048 A136835 A031166
KEYWORD
nonn
STATUS
approved