This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A323962 #7 Feb 16 2025 08:33:57
%S A323962 0,80,1526,34160,576060,8762880,123760560,1602344832,21025461600,
%T A323962 264121228800,3365570435040,42633973724160,535972460752320,
%U A323962 7005009151595520,88526770797830400,1212423433054986240,15530632515845568000,223695310100356300800,2930160761881213132800
%N A323962 Number of defective (binary) heaps on n elements with exactly six defects.
%C A323962 Or number of permutations p of [n] having exactly six indices i in {1,...,n} such that p(i) > p(floor(i/2)).
%H A323962 Alois P. Heinz, <a href="/A323962/b323962.txt">Table of n, a(n) for n = 6..200</a>
%H A323962 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Heap.html">Heap</a>
%H A323962 Wikipedia, <a href="https://en.wikipedia.org/wiki/Binary_heap">Binary heap</a>
%Y A323962 Column k=6 of A306343.
%Y A323962 Cf. A056971.
%K A323962 nonn
%O A323962 6,2
%A A323962 _Alois P. Heinz_, Feb 09 2019