A231657 Number of nX2 0..2 arrays with no element less than a strict majority of its horizontal, vertical and antidiagonal neighbors.

3, 15, 93, 458, 2163, 10789, 53813, 265397, 1311447, 6493700, 32130833, 158937397, 786355013, 3890673454, 19249161646, 95235762295, 471186213619, 2331226488364, 11533889645847, 57064690337149, 282331462742945, 1396854097460108

Offset: 1

Author

R. H. Hardin, Nov 12 2013

Keywords

• nonn

Comments

Column 2 of A231663

Examples

			Some solutions for n=7
..2..0....1..0....0..0....0..2....0..0....1..1....0..0....0..0....0..0....2..2
..0..0....0..0....2..0....0..0....1..0....1..2....0..2....0..0....1..0....2..0
..2..1....0..2....1..0....0..1....2..0....1..2....1..1....0..1....0..1....0..0
..1..1....0..1....0..0....2..2....0..1....1..1....1..1....1..0....0..0....2..0
..2..1....0..0....2..2....2..0....0..0....2..1....2..1....0..0....0..2....0..0
..0..0....0..1....2..0....0..0....0..0....2..1....1..0....0..1....2..1....2..1
..0..0....0..0....0..0....2..0....2..2....2..1....0..0....1..2....1..1....2..1
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 9*a(n-1) -28*a(n-2) +65*a(n-3) -167*a(n-4) +235*a(n-5) -237*a(n-6) +327*a(n-7) -345*a(n-8) +267*a(n-9) -198*a(n-10) +193*a(n-11) -88*a(n-12) +52*a(n-13) -20*a(n-14) +16*a(n-15)