A222884 Number of nX1 0..2 arrays with exactly floor(nX1/2) elements equal to at least one horizontal or vertical neighbor, with new values introduced in row major 0..2 order

1, 0, 0, 6, 16, 16, 40, 280, 768, 1440, 3808, 16352, 45056, 111104, 300672, 1072512, 2959360, 8281600, 22668800, 74866176, 206880768, 614068224, 1691502592, 5409544192, 14973206528, 45696688128, 126360084480, 398896128000

Offset

1,4

Comments

Column 1 of A222889

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Example

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

Crossrefs

Sequence in context: A291795 A301831 A183127 * A230949 A231023 A217186

Adjacent sequences: A222881 A222882 A222883 * A222885 A222886 A222887

Keyword

nonn

Author

R. H. Hardin Mar 08 2013

Status

approved