A197302 Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 4,4,0,2,1 for x=0,1,2,3,4

2, 10, 31, 98, 344, 1139, 3750, 12470, 41479, 137872, 458412, 1524061, 5066480, 16842888, 55992885, 186143874, 618820898, 2057222809, 6839076870, 22735974296, 75583965757, 251272978516, 835337355004, 2777013682031, 9231964714182

Offset

1,1

Comments

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

Column 3 of A197307

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) +3*a(n-3) +4*a(n-4) +2*a(n-5) +10*a(n-6) +6*a(n-7) -7*a(n-8) -23*a(n-9) -27*a(n-10) -23*a(n-11) +5*a(n-12) +29*a(n-13) +15*a(n-14) +2*a(n-15)

Example

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

Crossrefs

Sequence in context: A024456 A197452 A050927 * A263782 A011921 A212714

Adjacent sequences: A197299 A197300 A197301 * A197303 A197304 A197305

Keyword

nonn

Author

R. H. Hardin Oct 13 2011

Status

approved