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A180984 T(n,k)=number of nXk binary matrices with rows and columns in lexicographically strictly increasing order 1
2, 1, 1, 0, 3, 0, 0, 3, 3, 0, 0, 1, 15, 1, 0, 0, 0, 31, 31, 0, 0, 0, 0, 34, 234, 34, 0, 0, 0, 0, 21, 925, 925, 21, 0, 0, 0, 0, 7, 2366, 10706, 2366, 7, 0, 0, 0, 0, 1, 4305, 77079, 77079, 4305, 1, 0, 0, 0, 0, 0, 5845, 400672, 1411450, 400672, 5845, 0, 0, 0, 0, 0, 0, 6059, 1621242 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Table starts

.2.1..0....0........0..........0.............0...............0

.1.3..3....1........0..........0.............0...............0

.0.3.15...31.......34.........21.............7...............1

.0.1.31..234......925.......2366..........4305............5845

.0.0.34..925....10706......77079........400672.........1621242

.0.0.21.2366....77079....1411450......18068175.......179023089

.0.0..7.4305...400672...18068175.....539124281.....12176364503

.0.0..1.5845..1621242..179023089...12176364503....607445721710

.0.0..0.6059..5329869.1451615923..223274567811..24245093840300

.0.0..0.4830.14617117.9963573356.3463014573021.813139746187214

LINKS

R. H. Hardin, Table of n, a(n) for n=1..312

EXAMPLE

All solutions for 3X3

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

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

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

...

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

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

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

...

..0..1..1

..1..0..1

..1..1..1

CROSSREFS

Sequence in context: A253587 A110962 A065715 * A051628 A163540 A127967

Adjacent sequences:  A180981 A180982 A180983 * A180985 A180986 A180987

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin Sep 30 2010

STATUS

approved

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Last modified December 5 18:49 EST 2019. Contains 329768 sequences. (Running on oeis4.)