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A324071 Number of defective (binary) heaps on n elements where ten ancestor-successor pairs do not have the correct order. 2
0, 0, 0, 0, 0, 0, 0, 80, 3150, 36736, 359520, 3532800, 36115200, 383708160, 4247443200, 48673996800, 515675160000, 5654852403200, 64785924403200, 788119068672000, 9695238119424000, 125961866477568000, 1700829800017920000, 24580421999198208000 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,8

COMMENTS

Or number of permutations p of [n] having exactly ten pairs (i,j) in {1,...,n} X {1,...,floor(log_2(i))} such that p(i) > p(floor(i/2^j)).

LINKS

Alois P. Heinz, Table of n, a(n) for n = 0..200

Eric Weisstein's World of Mathematics, Heap

Wikipedia, Binary heap

Wikipedia, Permutation

CROSSREFS

Column k=10 of A306393.

Cf. A056971.

Sequence in context: A328875 A154307 A233950 * A017796 A035735 A035805

Adjacent sequences:  A324068 A324069 A324070 * A324072 A324073 A324074

KEYWORD

nonn

AUTHOR

Alois P. Heinz, Feb 13 2019

STATUS

approved

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Last modified May 28 16:37 EDT 2022. Contains 354119 sequences. (Running on oeis4.)