A252853 Number of (n+2)X(n+2) 0..2 arrays with every consecutive three elements in every row, column, diagonal and antidiagonal having exactly two distinct values, and new values 0 upwards introduced in row major order

117, 432, 1197, 3582, 14229, 60588, 275598, 1334322, 6954849, 38574297, 227384559, 1439372097

Offset

1,1

Comments

Diagonal of A252861

Links

Table of n, a(n) for n=1..12.

Example

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

Crossrefs

Sequence in context: A156884 A255022 A217798 * A273125 A327599 A326064

Adjacent sequences: A252850 A252851 A252852 * A252854 A252855 A252856

Keyword

nonn

Author

R. H. Hardin, Dec 23 2014

Status

approved