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A181234 Number of (2*n)Xn binary matrices with all row sums equal and all column sums equal 0
2, 8, 182, 49772, 113400002, 4027811102702, 1237505791330809002 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A181236

LINKS

Table of n, a(n) for n=1..7.

EXAMPLE

Some solutions for 6X3

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

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

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

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

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

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

CROSSREFS

Sequence in context: A009713 A213200 A009377 * A156526 A009505 A028368

Adjacent sequences:  A181231 A181232 A181233 * A181235 A181236 A181237

KEYWORD

nonn

AUTHOR

R. H. Hardin Oct 10 2010

STATUS

approved

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Last modified November 23 22:48 EST 2014. Contains 249866 sequences.