A196691 Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,1,3,0,4 for x=0,1,2,3,4

3, 11, 76, 408, 2025, 10548, 55431, 289038, 1506376, 7857827, 40992713, 213825921, 1115337571, 5817828688, 30347027526, 158296067515, 825703442256, 4307033134922, 22466340292902, 117188887827705, 611280485474823

Offset

1,1

Comments

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

Column 3 of A196696

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +8*a(n-2) +32*a(n-3) +54*a(n-4) +88*a(n-5) +28*a(n-6) -a(n-7) -10*a(n-8) -18*a(n-9) -a(n-11) -a(n-12) for n>13

Example

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

Crossrefs

Sequence in context: A290025 A239658 A181388 * A197064 A117765 A220146

Adjacent sequences: A196688 A196689 A196690 * A196692 A196693 A196694

Keyword

nonn

Author

R. H. Hardin Oct 05 2011

Status

approved