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

%I #3 Mar 31 2012 12:35:49

%S 1,1,1,0,2,1,0,1,4,1,0,1,6,6,1,0,0,10,20,9,1,0,0,9,71,49,12,1,0,0,6,

%T 200,368,109,16,1,0,0,3,450,2403,1502,222,20,1,0,0,1,780,13059,19929,

%U 5208,412,25,1,0,0,0,1042,60488,238535,135984,15983,712,30,1,0,0,0,1084

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

%C Table starts

%C .1..1....0......0........0..........0............0..............0

%C .1..2....1......1........0..........0............0..............0

%C .1..4....6.....10........9..........6............3..............1

%C .1..6...20.....71......200........450..........780...........1042

%C .1..9...49....368.....2403......13059........60488.........221320

%C .1.12..109...1502....19929.....238535......2448773.......21398553

%C .1.16..222...5208...135984....3267300.....73506103.....1350956543

%C .1.20..412..15983...755144...36506260...1632383886....64732546521

%C .1.25..712..44485..3831820..348892547..32320317217..2541063599189

%C .1.30.1177.114320.16788240.2938265005.519815199311.85375670050862

%H R. H. Hardin, <a href="/A180983/b180983.txt">Table of n, a(n) for n=1..199</a>

%e All solutions for 3X4

%e ..0..0..0..1....0..0..0..1....0..0..0..1....0..0..1..1....0..0..1..1

%e ..0..0..1..1....0..1..1..0....0..1..1..1....0..0..1..1....0..1..0..1

%e ..0..1..1..1....1..0..1..1....1..0..1..0....0..1..0..1....0..1..1..0

%e ...

%e ..0..0..1..1....0..0..1..1....0..0..1..1....0..0..1..1....0..0..1..1

%e ..0..1..0..1....0..1..0..1....0..1..0..1....0..1..0..0....0..1..0..1

%e ..0..1..0..1....1..0..1..0....1..0..0..1....1..1..0..1....1..1..0..0

%K nonn,tabl

%O 1,5

%A _R. H. Hardin_ Sep 30 2010