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A323963
Number of defective (binary) heaps on n elements with exactly seven defects.
2
0, 210, 7616, 185460, 4200960, 77887920, 1310267904, 21025461600, 314958758400, 4765553385120, 69086614338560, 1013373907056960, 14714554645140480, 212868974122848000, 3168605413206097920, 45787509175434048000, 705241846739554713600, 10297540417675899801600
OFFSET
7,2
COMMENTS
Or number of permutations p of [n] having exactly seven indices i in {1,...,n} such that p(i) > p(floor(i/2)).
LINKS
Eric Weisstein's World of Mathematics, Heap
Wikipedia, Binary heap
CROSSREFS
Column k=7 of A306343.
Cf. A056971.
Sequence in context: A061133 A087977 A185042 * A023905 A035840 A140904
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Feb 09 2019
STATUS
approved