A209961 Number of (n+1)X(n+1) 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, 25435, 53890394, 351689776895, 8191570949391204, 721612821437109284511, 247946490679458336910844453

Offset

1,2

Comments

Diagonal of A209969

Links

Table of n, a(n) for n=1..8.

Example

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

Crossrefs

Sequence in context: A336248 A359054 A359052 * A302396 A208186 A316677

Adjacent sequences: A209958 A209959 A209960 * A209962 A209963 A209964

Keyword

nonn

Author

R. H. Hardin, Mar 16 2012

Status

approved