A180977 - OEIS

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A180977

T(n,k)=number of nXk binary matrices with floor((n*k)/2) 1's and rows and columns in lexicographically strictly increasing order

1, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 5, 1, 0, 0, 0, 8, 8, 0, 0, 0, 0, 9, 50, 9, 0, 0, 0, 0, 6, 181, 181, 6, 0, 0, 0, 0, 3, 438, 1823, 438, 3, 0, 0, 0, 0, 1, 775, 11700, 11700, 775, 1, 0, 0, 0, 0, 0, 1039, 58090, 189359, 58090, 1039, 0, 0, 0, 0, 0, 0, 1084, 218120, 2218249, 2218249

(list; table; graph; refs; listen; history; text; internal format)

OFFSET

1,13

COMMENTS

Table starts

.1.1.0....0.......0..........0............0..............0.................0

.1.1.1....1.......0..........0............0..............0.................0

.0.1.5....8.......9..........6............3..............1.................0

.0.1.8...50.....181........438..........775...........1039..............1084

.0.0.9..181....1823......11700........58090.........218120............707425

.0.0.6..438...11700.....189359......2218249.......20523612.........157471741

.0.0.3..775...58090....2218249.....61746973.....1247701323.......22218184979

.0.0.1.1039..218120...20523612...1247701323....57086318681.....2123810796163

.0.0.0.1084..707425..157471741..22218184979..2123810796163...174484293356777

.0.0.0..887.1835737.1032413434.315303186865.67142312629555.11201887329999615

LINKS

R. H. Hardin, Table of n, a(n) for n=1..220

EXAMPLE

All solutions for 3X4

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

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

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

...

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

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

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

CROSSREFS

Sequence in context: A129205 A327581 A098173 * A371761 A269129 A320606

Adjacent sequences: A180974 A180975 A180976 * A180978 A180979 A180980

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin Sep 30 2010

STATUS

approved