A222718 Number of nX2 0..3 arrays with exactly floor(nX2/2) elements equal to at least one horizontal, vertical or antidiagonal neighbor, with new values introduced in row major 0..3 order

0, 6, 30, 666, 6524, 103378, 1250904, 17976376, 235892592, 3296371800, 44713314784, 621198984864, 8554092568512, 118954438125472, 1651089670102400, 23021868920182656, 321109217833684736, 4490028930013194112

Offset

1,2

Comments

Column 2 of A222722

Links

R. H. Hardin, Table of n, a(n) for n = 1..209

Example

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

Crossrefs

Sequence in context: A075591 A130075 A066388 * A200894 A202861 A088256

Adjacent sequences: A222715 A222716 A222717 * A222719 A222720 A222721

Keyword

nonn

Author

R. H. Hardin Mar 03 2013

Status

approved