A197230 Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 4,3,0,1,2 for x=0,1,2,3,4

2, 12, 55, 242, 1178, 5355, 24723, 116440, 545287, 2548432, 11939565, 55931989, 261856867, 1226207807, 5742642388, 26891481148, 125926466092, 589702469437, 2761498731050, 12931647025852, 60557080572253, 283580433219551

Offset

1,1

Comments

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

Column 3 of A197235

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +3*a(n-2) +38*a(n-3) +40*a(n-4) +10*a(n-5) -150*a(n-6) -375*a(n-7) -175*a(n-8) +637*a(n-9) +2013*a(n-10) +1368*a(n-11) -1614*a(n-12) -4361*a(n-13) -4043*a(n-14) +946*a(n-15) +4156*a(n-16) +3551*a(n-17) +552*a(n-18) -881*a(n-19) -629*a(n-20) -1033*a(n-21) +508*a(n-22)

Example

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

Crossrefs

Sequence in context: A122676 A038175 A181541 * A025171 A342319 A127214

Adjacent sequences: A197227 A197228 A197229 * A197231 A197232 A197233

Keyword

nonn

Author

R. H. Hardin Oct 12 2011

Status

approved