A197245 Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 0,0,1,1,1 for x=0,1,2,3,4

1, 8, 3, 53, 110, 227, 1035, 2004, 7529, 20633, 53902, 172997, 474139, 1395792, 4009631, 11336881, 33563326, 95906965, 275694011, 796470870, 2294495057, 6647188965, 19110664400, 55033208033, 159018294491, 458707454692

Offset

1,2

Comments

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

Column 3 of A197250

Links

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

Formula

Empirical: a(n) = a(n-2) +9*a(n-3) +26*a(n-4) +58*a(n-5) -25*a(n-6) -148*a(n-7) -104*a(n-8) -114*a(n-9) +55*a(n-10) -149*a(n-11) +186*a(n-12) -9*a(n-13) +39*a(n-14) -55*a(n-15) +21*a(n-16) +a(n-17) +2*a(n-18) -a(n-19) for n>20

Example

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

Crossrefs

Sequence in context: A049074 A286034 A256046 * A302462 A303244 A038281

Adjacent sequences: A197242 A197243 A197244 * A197246 A197247 A197248

Keyword

nonn

Author

R. H. Hardin Oct 12 2011

Status

approved