A324071 Number of defective (binary) heaps on n elements where ten ancestor-successor pairs do not have the correct order.

0, 0, 0, 0, 0, 0, 0, 80, 3150, 36736, 359520, 3532800, 36115200, 383708160, 4247443200, 48673996800, 515675160000, 5654852403200, 64785924403200, 788119068672000, 9695238119424000, 125961866477568000, 1700829800017920000, 24580421999198208000

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