A183306 Half the number of nX5 binary arrays with no element equal to a strict majority of its horizontal and vertical neighbors.

3, 9, 42, 178, 910, 4212, 19899, 94217, 445859, 2113257, 10006598, 47387904, 224418390, 1062810762, 5033385029, 23837475807, 112891241315, 534638647159, 2531982065694, 11991154349342, 56788620500294, 268943860673076

Offset: 1

Author

R. H. Hardin Jan 03 2011

Keywords

• nonn

Comments

Column 5 of A183312

Examples

			Some solutions with a(1,1)=0 for 5X4
..0..0..1..0....0..1..1..0....0..1..0..1....0..1..1..0....0..1..0..1
..1..1..0..1....1..0..0..1....0..1..0..0....1..0..0..1....1..0..0..1
..0..1..1..0....0..1..1..0....1..0..1..1....1..0..0..1....0..1..1..0
..1..0..0..1....1..0..0..1....0..1..1..0....0..1..1..0....1..0..1..1
..1..0..1..0....0..1..0..1....1..0..0..1....1..0..1..0....0..1..0..0
		

Links

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

Formula

Empirical: a(n)=9*a(n-1)-26*a(n-2)+24*a(n-3)+47*a(n-4)-157*a(n-5)-43*a(n-6)+641*a(n-7)-643*a(n-8)-952*a(n-9)+3460*a(n-10)-2021*a(n-11)-2111*a(n-12)+2715*a(n-13)-1249*a(n-14)-4657*a(n-15)-1514*a(n-16)+1961*a(n-17)-1230*a(n-18)+6713*a(n-19)+8832*a(n-20)+10212*a(n-21)+1971*a(n-22)-6552*a(n-23)-2819*a(n-24)-2898*a(n-25)-973*a(n-26)+302*a(n-27)+433*a(n-28)+286*a(n-29) for n>31