A230646 Number of n X n 0..2 white square subarrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value 2-x(i,j)

0, 3, 3, 123, 1635, 337977, 31908483, 40860127671, 24818871787539, 201844710508818147, 781457119775191627041, 40464088148356899296269059, 997750456877626717987299707229

Offset

1,2

Comments

Diagonal of A230652

Links

Table of n, a(n) for n=1..13.

Example

Some solutions for n=5
..0..x..0..x..2....1..x..2..x..2....0..x..0..x..1....2..x..2..x..0
..x..2..x..0..x....x..1..x..0..x....x..2..x..1..x....x..0..x..2..x
..0..x..2..x..2....2..x..2..x..1....2..x..0..x..1....2..x..1..x..0
..x..1..x..2..x....x..0..x..1..x....x..0..x..1..x....x..1..x..0..x
..1..x..0..x..0....2..x..1..x..1....2..x..2..x..1....1..x..1..x..2

Crossrefs

Sequence in context: A176614 A173797 A173127 * A006845 A071536 A094755

Adjacent sequences: A230643 A230644 A230645 * A230647 A230648 A230649

Keyword

nonn

Author

R. H. Hardin, Oct 27 2013

Status

approved