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%I #6 Feb 24 2019 15:38:30
%S 0,0,0,0,0,16,120,720,4830,31360,211680,1555200,11880000,95293440,
%T 815443200,7687680000,60432372000,530552422400,4945330790400,
%U 51912327168000,496766020608000,5425624055808000,61093281300480000,781258429366272000,8157685988035584000
%N Number of defective (binary) heaps on n elements where five ancestor-successor pairs do not have the correct order.
%C Or number of permutations p of [n] having exactly five pairs (i,j) in {1,...,n} X {1,...,floor(log_2(i))} such that p(i) > p(floor(i/2^j)).
%H Alois P. Heinz, <a href="/A324066/b324066.txt">Table of n, a(n) for n = 0..200</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Heap.html">Heap</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Binary_heap">Binary heap</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Permutation">Permutation</a>
%Y Column k=5 of A306393.
%Y Cf. A056971.
%K nonn
%O 0,6
%A _Alois P. Heinz_, Feb 13 2019