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A195643
Number of lower triangles of an n X n 0..7 array with all row sums equal to the length of the row and all column sums equal to the length of the column
1
1, 1, 3, 19, 391, 25532, 5539434, 4116290300, 10699674783969, 98827025484631957, 3284291571314714878300
OFFSET
1,3
COMMENTS
Column 7 of A194644
EXAMPLE
Some solutions for n=7
..1..............1..............1..............1..............1
..1.1............0.2............2.0............2.0............2.0
..0.3.0..........0.3.0..........3.0.0..........2.1.0..........2.1.0
..4.0.0.0........2.1.1.0........0.2.2.0........1.3.0.0........2.2.0.0
..0.2.2.0.1......2.0.1.1.1......1.1.2.0.1......1.2.2.0.0......0.1.0.3.1
..1.0.1.0.2.2....2.0.2.0.2.0....0.3.0.1.2.0....0.0.2.4.0.0....0.1.4.0.1.0
..0.0.2.4.0.0.1..0.0.1.3.0.2.1..0.0.1.3.0.2.1..0.0.1.0.3.2.1..0.1.1.1.1.2.1
CROSSREFS
Sequence in context: A195640 A195641 A195642 * A195638 A041951 A365362
KEYWORD
nonn
AUTHOR
R. H. Hardin Sep 21 2011
STATUS
approved