A183404 Number of nX3 binary arrays with each sum of a(1..i,1..j) no greater than i*j/2

3, 21, 114, 850, 5354, 40832, 274911, 2120988, 14827787, 115207396, 825114785, 6441358454, 46915800558, 367505583063, 2710102446879, 21283753145043, 158451414945246, 1246900992786465, 9352863302296454, 73719397766360957

Offset

1,1

Comments

Column 3 of A183407

Links

R. H. Hardin, Table of n, a(n) for n = 1..46

Example

Some solutions for 4X3
..0..0..0....0..0..0....0..0..1....0..0..0....0..0..0....0..1..0....0..0..1
..0..0..0....1..0..0....0..1..0....0..0..1....1..0..1....0..1..0....0..1..0
..0..1..0....0..0..0....0..0..1....1..1..0....0..1..1....0..1..0....0..0..0
..0..1..0....1..1..1....0..0..0....1..1..1....1..0..1....0..0..0....1..1..1

Crossrefs

Sequence in context: A043012 A122120 A080952 * A309670 A121140 A005057

Adjacent sequences: A183401 A183402 A183403 * A183405 A183406 A183407

Keyword

nonn

Author

R. H. Hardin Jan 04 2011

Status

approved