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A180999 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 odd number of 1s 0
1, 1, 1, 3, 21, 613, 58894, 17001258, 14824281524, 39871721434052 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

Diagonal of A181000

LINKS

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

EXAMPLE

All solutions for 4X4

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

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

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

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

CROSSREFS

Sequence in context: A128679 A292331 A111432 * A181003 A093549 A012044

Adjacent sequences:  A180996 A180997 A180998 * A181000 A181001 A181002

KEYWORD

nonn

AUTHOR

R. H. Hardin Sep 30 2010

STATUS

approved

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Last modified October 15 05:43 EDT 2019. Contains 328026 sequences. (Running on oeis4.)