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Number of defective (binary) heaps on n elements with exactly ten defects.
2

%I #6 Feb 09 2019 21:26:45

%S 0,19200,947760,49680576,1744142400,60169824000,1646888944800,

%T 42633973724160,1013373907056960,22797317814635520,502986050203680000,

%U 10556482426015426560,222685725334400064000,4535040919258899456000,92995172484979478630400,1880492299058130490163200

%N Number of defective (binary) heaps on n elements with exactly ten defects.

%C Or number of permutations p of [n] having exactly ten indices i in {1,...,n} such that p(i) > p(floor(i/2)).

%H Alois P. Heinz, <a href="/A323966/b323966.txt">Table of n, a(n) for n = 10..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>

%Y Column k=10 of A306343.

%Y Cf. A056971.

%K nonn

%O 10,2

%A _Alois P. Heinz_, Feb 09 2019