A184139 Number of nX4 binary arrays with rows and columns in nondecreasing order.

5, 25, 130, 650, 2942, 11819, 42305, 136564, 402910, 1099694, 2805530, 6748066, 15412437, 33626131, 70430778, 142218719, 277853339, 526833235, 972034814, 1749218190, 3076360192, 5297051455, 8943742419, 14828643610, 24172697276

Offset: 1

Author

R. H. Hardin Jan 09 2011

Keywords

• nonn

Comments

Column 4 of A180985

Examples

			Some solutions for 3X4
..0..0..1..1....0..0..0..0....0..1..1..1....0..0..1..1....0..0..0..1
..1..1..0..0....0..0..1..1....1..0..0..1....0..1..0..1....0..0..0..1
..1..1..1..1....1..1..1..1....1..0..1..1....1..1..1..0....0..0..0..1
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

Empirical: a(n)=16*a(n-1)-120*a(n-2)+560*a(n-3)-1820*a(n-4)+4368*a(n-5)-8008*a(n-6)+11440*a(n-7)-12870*a(n-8)+11440*a(n-9)-8008*a(n-10)+4368*a(n-11)-1820*a(n-12)+560*a(n-13)-120*a(n-14)+16*a(n-15)-a(n-16) (=polynomial degree 15)