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A213956
Number of n X n 0..2 matrices with row and column i=1..n having sum <= i*2
0
3, 42, 3186, 1299735, 2860343784, 34107691901433, 2211749000480369037, 782349734245964422491828
OFFSET
1,1
COMMENTS
Column 2 of A213962
EXAMPLE
Some solutions for n=4
..0..2..0..0....2..0..0..0....2..0..0..0....2..0..0..0....2..0..0..0
..0..1..2..0....0..1..0..0....0..1..1..0....0..2..2..0....0..1..0..1
..1..0..2..0....0..1..1..0....0..1..0..2....0..0..1..1....0..2..1..0
..0..1..1..2....0..1..2..2....0..2..0..1....0..0..2..0....0..1..0..0
CROSSREFS
Sequence in context: A210929 A083402 A145984 * A157552 A058808 A155210
KEYWORD
nonn
AUTHOR
R. H. Hardin Jun 28 2012
STATUS
approved