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%I #4 Mar 31 2012 12:36:12
%S 0,1,8,66,722,9955,165252,3221806,72445292,1851203574,53113148720,
%T 1694163830194,59579694687012
%N Number of (2*n)Xn binary arrays with nonzero rows in decreasing order, no more than 3 ones in any row and exactly 2 ones in every column
%C Row 2 of A188449
%e Some solutions for 6X3
%e ..1..1..1....1..1..0....1..1..1....1..0..1....1..1..0....1..1..1....1..1..1
%e ..1..0..1....1..0..1....1..0..0....1..0..0....1..0..1....1..0..0....1..1..0
%e ..0..1..0....0..1..0....0..1..1....0..1..1....0..1..1....0..1..0....0..0..1
%e ..0..0..0....0..0..1....0..0..0....0..1..0....0..0..0....0..0..1....0..0..0
%e ..0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0
%e ..0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0
%K nonn
%O 1,3
%A _R. H. Hardin_ Mar 31 2011
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