A197452 Number of nX3 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 3,3,0,2,2 for x=0,1,2,3,4

2, 10, 31, 84, 290, 923, 2887, 9216, 29288, 92868, 294893, 936361, 2972409, 9436595, 29959267, 95112260, 301956214, 958634094, 3043413512, 9662045566, 30674490204, 97383543481, 309167462063, 981526438497, 3116091639355, 9892781977749

Offset

1,1

Comments

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

Column 3 of A197457

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +4*a(n-2) +3*a(n-3) -7*a(n-4) -18*a(n-5) -5*a(n-6) +18*a(n-7) +31*a(n-8) +20*a(n-9) -5*a(n-10) -25*a(n-11) -18*a(n-12) -7*a(n-13) +3*a(n-14) +2*a(n-15)

Example

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

Crossrefs

Sequence in context: A051747 A193008 A024456 * A050927 A197302 A263782

Adjacent sequences: A197449 A197450 A197451 * A197453 A197454 A197455

Keyword

nonn

Author

_R. H. Hardin_ Oct 15 2011

Status

approved