A209963 Number of (n+1)X3 0..3 arrays containing all values 0..3 with every 2X2 subblock having one or two distinct values, and new values 0..3 introduced in row major order

0, 26, 665, 13529, 235614, 3745144, 56080379, 806021187, 11250016056, 153671659498, 2065329135285, 27415388492285, 360428944284258, 4702933675666684, 60999760074268959, 787454521196946391

Offset

1,2

Comments

Column 2 of A209969

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 33*a(n-1) -374*a(n-2) +1586*a(n-3) -1093*a(n-4) -4559*a(n-5) +7212*a(n-6) -420*a(n-7) -4336*a(n-8) +2208*a(n-9) -256*a(n-10)

Example

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

Crossrefs

Sequence in context: A170707 A170745 A218728 * A158542 A171331 A097309

Adjacent sequences: A209960 A209961 A209962 * A209964 A209965 A209966

Keyword

nonn

Author

R. H. Hardin Mar 16 2012

Status

approved