A197345 Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,3,1,1,0 for x=0,1,2,3,4

1, 9, 18, 83, 245, 914, 3155, 11287, 39850, 141325, 501819, 1782870, 6328399, 22463277, 79770690, 283288919, 1005900951, 3571642082, 12682562591, 45035370321, 159915993486, 567839908711, 2016337387209, 7159825934978

Offset

1,2

Comments

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

Column 3 of A197350

Links

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

Formula

Empirical: a(n) = a(n-1) +2*a(n-2) +8*a(n-3) +52*a(n-4) +40*a(n-5) +33*a(n-6) -34*a(n-7) -471*a(n-8) -603*a(n-9) -944*a(n-10) -786*a(n-11) +1306*a(n-12) +1460*a(n-13) +1840*a(n-14) +2248*a(n-15) -1768*a(n-16) -1536*a(n-17) -192*a(n-18)

Example

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

Crossrefs

Sequence in context: A361082 A166640 A140149 * A186951 A176201 A186443

Adjacent sequences: A197342 A197343 A197344 * A197346 A197347 A197348

Keyword

nonn

Author

R. H. Hardin Oct 13 2011

Status

approved