A183407 T(n,k)=Number of nXk binary arrays with each sum of a(1..i,1..j) no greater than i*j/2

1, 2, 2, 3, 7, 3, 6, 21, 21, 6, 10, 78, 114, 78, 10, 20, 260, 850, 850, 260, 20, 35, 988, 5354, 12203, 5354, 988, 35, 70, 3458, 40832, 154079, 154079, 40832, 3458, 70, 126, 13300, 274911, 2291035, 3770481, 2291035, 274911, 13300, 126, 252, 47880, 2120988

Offset

1,2

Comments

Table starts

...1......2.........3............6.............10................20

...2......7........21...........78............260...............988

...3.....21.......114..........850...........5354.............40832

...6.....78.......850........12203.........154079...........2291035

..10....260......5354.......154079........3770481.........112353512

..20....988.....40832......2291035......112353512........6583423572

..35...3458....274911.....30897341.....2965955665......348054260961

..70..13300...2120988....467710777....89945894383....20844200882158

.126..47880..14827787...6547006490..2477411142245..1149400416641961

.252.185535.115207396.100186985054.75930571035939.69745557672260827

Links

R. H. Hardin, Table of n, a(n) for n = 1..158

Example

Some solutions for 5X4
..0..1..0..0....0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..1
..0..0..0..1....1..0..0..1....0..1..1..0....0..0..1..1....0..0..1..0
..0..1..1..0....0..1..0..1....1..0..0..1....0..1..0..1....1..0..1..0
..0..0..0..1....0..0..0..0....0..0..1..1....1..1..0..0....1..1..0..0
..1..0..1..1....0..0..1..1....1..0..0..0....1..1..1..0....0..1..1..0

Crossrefs

Column 1 is A001405

Sequence in context: A208151 A203362 A368219 * A222838 A222944 A222871

Adjacent sequences: A183404 A183405 A183406 * A183408 A183409 A183410

Keyword

nonn,tabl

Author

R. H. Hardin Jan 04 2011

Status

approved