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A181003
Number of n X n binary matrices with rows and columns each in strictly increasing order as binary numbers and each row and column having an even number of 1s
0
1, 0, 1, 3, 21, 632, 58741, 16972746, 14821714373, 39880712826780
OFFSET
1,4
COMMENTS
Diagonal of A181004
EXAMPLE
All solutions for 4X4
..0..0..0..0....0..0..1..1....0..0..1..1
..0..0..1..1....0..1..0..1....0..1..0..1
..0..1..0..1....1..0..1..0....1..0..0..1
..0..1..1..0....1..1..0..0....1..1..1..1
CROSSREFS
Sequence in context: A292331 A111432 A180999 * A093549 A012044 A350513
KEYWORD
nonn
AUTHOR
R. H. Hardin Sep 30 2010
STATUS
approved