A222885 Number of nX2 0..2 arrays with exactly floor(nX2/2) elements equal to at least one horizontal or vertical neighbor, with new values introduced in row major 0..2 order

0, 4, 22, 184, 1222, 9918, 73038, 571736, 4390202, 34351802, 267982304, 2106587634, 16576619646, 130932847630, 1036002954358, 8216574460288, 65272910779558, 519408134342898, 4138939523056050, 33024940436137874, 263814619538403032

Offset

1,2

Comments

Column 2 of A222889

Links

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

Example

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

Crossrefs

Sequence in context: A125863 A004115 A362747 * A235329 A220231 A112370

Adjacent sequences: A222882 A222883 A222884 * A222886 A222887 A222888

Keyword

nonn

Author

R. H. Hardin Mar 08 2013

Status

approved