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A181006 Number of (n+2)xn 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
0, 0, 0, 0, 123, 16675, 5752742, 5565513638, 15996779979401, 141854932507575253 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

Subdiagonal 2 of A181004

LINKS

Table of n, a(n) for n=1..10.

EXAMPLE

Some solutions for 7X5

..0..0..0..0..0....0..0..0..0..0....0..0..0..0..0....0..0..0..0..0

..0..0..0..1..1....0..0..0..1..1....0..0..0..1..1....0..0..0..1..1

..0..0..1..0..1....0..0..1..0..1....0..0..1..0..1....0..0..1..0..1

..0..0..1..1..0....0..0..1..1..0....0..0..1..1..0....0..0..1..1..0

..0..1..0..1..0....0..1..0..1..0....0..1..1..0..0....0..1..1..0..0

..1..0..0..1..0....1..0..1..0..0....1..0..0..1..0....1..0..1..0..0

..1..1..0..0..0....1..1..1..1..0....1..1..1..1..0....1..1..0..0..0

CROSSREFS

Sequence in context: A095761 A121917 A049670 * A289331 A334181 A033522

Adjacent sequences:  A181003 A181004 A181005 * A181007 A181008 A181009

KEYWORD

nonn

AUTHOR

R. H. Hardin Sep 30 2010

STATUS

approved

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Last modified August 9 12:53 EDT 2022. Contains 356026 sequences. (Running on oeis4.)