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%I #4 Aug 07 2012 11:36:32
%S 1,20,420,23100,1051050,85765680,5703417720,577185873264,
%T 48236247979920,5595404765670720,545152292883918720,
%U 69506917342699636800,7562187114225380722800,1033498905610802032116000
%N Number of permutations of 0..floor((n*6-1)/2) on even squares of an nX6 array such that each row and column of even squares is increasing
%C Column 6 of A215292
%H R. H. Hardin, <a href="/A215290/b215290.txt">Table of n, a(n) for n = 1..210</a>
%F f3=floor((n+1)/2)
%F f4=floor(n/2)
%F a(n) = A060854(3,f3)*A060854(3,f4)*binomial(3*f3+3*f4,3*f3)
%e Some solutions for n=4
%e ..0..x..2..x..6..x....1..x..6..x..7..x....1..x..2..x..7..x....0..x..2..x..6..x
%e ..x..1..x..3..x..5....x..0..x..2..x..4....x..0..x..4..x.10....x..3..x..5..x..7
%e ..4..x..9..x.10..x....9..x.10..x.11..x....3..x..6..x..8..x....1..x..9..x.11..x
%e ..x..7..x..8..x.11....x..3..x..5..x..8....x..5..x..9..x.11....x..4..x..8..x.10
%K nonn
%O 1,2
%A _R. H. Hardin_ Aug 07 2012
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