A197532 Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,0,1,0,0 for x=0,1,2,3,4.

4, 16, 56, 216, 868, 3500, 14085, 56842, 229706, 928664, 3755722, 15191220, 61451640, 248596817, 1005703793, 4068662528, 16460279703, 66592450774, 269410213656, 1089943115100, 4409547400430, 17839571907124, 72173035560719

Offset: 1

Author

R. H. Hardin Oct 16 2011

Keywords

• nonn

Comments

Every 0 is next to 0 2's, every 1 is next to 1 0's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 0's

Column 3 of A197537

Examples

			Some solutions for n=4
..0..0..1....1..0..0....0..0..0....0..3..0....1..1..1....1..0..0....0..0..0
..1..1..1....2..3..0....3..0..3....0..0..3....0..0..0....1..0..3....0..0..3
..1..1..0....1..0..0....0..3..0....3..0..0....3..0..3....2..3..0....0..0..0
..0..1..1....1..0..0....1..2..1....0..3..0....0..0..0....1..0..0....1..1..1
		

Links

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

Formula

Empirical: a(n) = 4*a(n-1) +5*a(n-2) -15*a(n-3) -21*a(n-4) +3*a(n-5) +28*a(n-6) +32*a(n-7) -5*a(n-8) -57*a(n-9) +10*a(n-10) +90*a(n-11) +44*a(n-12) -14*a(n-13) -101*a(n-14) -56*a(n-15) +46*a(n-16) +14*a(n-17) +11*a(n-18) -20*a(n-19) +9*a(n-20) +10*a(n-21) -9*a(n-22) -a(n-25)