%I #5 Apr 13 2022 20:24:52
%S 1,10,200,13440,2097900,442030200,257134170000,122150707608000,
%T 111415794466080000,163780469919918720000
%N Number of permutations of 3 copies of 1..n with no element e[i>=2]<e[1+floor((i-2)/5)] (5-way heap).
%Y Simple 2-way heap A056971.
%K nonn
%O 1,2
%A _R. H. Hardin_, May 17 2010
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