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A180985 Array T(n,k) = number of n X k binary matrices with rows and columns in lexicographically nondecreasing order. 8
2, 3, 3, 4, 7, 4, 5, 14, 14, 5, 6, 25, 45, 25, 6, 7, 41, 130, 130, 41, 7, 8, 63, 336, 650, 336, 63, 8, 9, 92, 785, 2942, 2942, 785, 92, 9, 10, 129, 1682, 11819, 24520, 11819, 1682, 129, 10, 11, 175, 3351, 42305, 183010, 183010, 42305, 3351, 175, 11, 12, 231, 6280, 136564 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Table starts:

..2...3.....4.......5.........6...........7.............8................9

..3...7....14......25........41..........63............92..............129

..4..14....45.....130.......336.........785..........1682.............3351

..5..25...130.....650......2942.......11819.........42305...........136564

..6..41...336....2942.....24520......183010.......1202234..........6979061

..7..63...785...11819....183010.....2625117......33345183........371484319

..8..92..1682...42305...1202234....33345183.....836488618......18470742266

..9.129..3351..136564...6979061...371484319...18470742266.....818230288201

.10.175..6280..402910..36211867..3651371519..358194085968...31887670171373

.11.231.11176.1099694.170079565.32017940222.6148026957098.1096628939510047

LINKS

R. H. Hardin, Table of n, a(n) for n=1..311

EXAMPLE

All solutions for 3 X 3:

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

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

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

...

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

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

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

...

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

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

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

...

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

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

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

...

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

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

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

...

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

..1..1..1....1..1..1

..1..1..1....1..1..1

CROSSREFS

Cf. A089006 (diagonal).

Sequence in context: A248944 A267245 A266428 * A227385 A049790 A222188

Adjacent sequences:  A180982 A180983 A180984 * A180986 A180987 A180988

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Sep 30 2010

STATUS

approved

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Last modified November 30 18:22 EST 2020. Contains 338807 sequences. (Running on oeis4.)