A230941 Number of (n+3)X(n+3) 0..3 white square subarrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, and upper left element zero

6, 34, 8374, 606224, 584293702, 295706164414, 2042677948725090

Offset

1,1

Comments

Diagonal of A230949

Links

Table of n, a(n) for n=1..7.

Example

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

Crossrefs

Sequence in context: A161323 A003423 A230936 * A359571 A145000 A354792

Adjacent sequences: A230938 A230939 A230940 * A230942 A230943 A230944

Keyword

nonn

Author

R. H. Hardin, Nov 01 2013

Status

approved