A183548 Number of nX3 0..2 arrays with each element equal to either the maximum or the minimum of its horizontal and vertical neighbors.

3, 71, 583, 5287, 46841, 417809, 3721925, 33169105, 295565367, 2633809823, 23469955635, 209141864227, 1863672026457, 16607262667561, 147988036529381, 1318727810932497, 11751240682625031, 104715815140064955

Offset: 1

Author

R. H. Hardin Jan 05 2011

Keywords

• nonn

Comments

Column 3 of A183554

Examples

			Some solutions for 5X3
..2..2..2....0..0..0....1..1..1....2..2..1....0..2..2....1..1..1....0..0..1
..0..0..0....2..2..0....1..1..1....0..2..1....0..2..1....2..2..0....0..0..1
..0..2..2....2..0..0....1..1..1....0..0..1....2..2..1....2..2..0....2..2..0
..2..1..2....0..0..0....0..2..0....0..0..1....2..2..2....2..0..0....0..2..0
..2..1..1....1..1..0....0..2..0....0..0..1....2..0..0....0..0..0....0..2..2
		

Links

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

Formula

Empirical: a(n)=12*a(n-1)-26*a(n-2)-33*a(n-3)+204*a(n-4)-244*a(n-5)-339*a(n-6)+256*a(n-7)+1324*a(n-8)-559*a(n-9)-4420*a(n-10)+5965*a(n-11)+8096*a(n-12)-10724*a(n-13)-1370*a(n-14)+5054*a(n-15)-15721*a(n-16)+9505*a(n-17)-7190*a(n-18)-20835*a(n-19)+2723*a(n-20)+1324*a(n-21)+2340*a(n-22)+2496*a(n-23)-1996*a(n-24)-452*a(n-25)+2222*a(n-26)+273*a(n-27)-941*a(n-28)+334*a(n-29)-61*a(n-30)-44*a(n-31)+12*a(n-32)