A222373 Number of nX2 0..3 arrays with no more than floor(nX2/2) elements unequal to at least one horizontal or vertical neighbor, with new values introduced in row major 0..3 order

1, 1, 5, 18, 63, 234, 1163, 4953, 24021, 109395, 536457, 2526558, 12324313, 59135699, 288057673, 1396084937, 6800380165, 33152287976, 161670473265, 790996243845, 3863624579433, 18948369852560, 92716137764021, 455475835479225

Offset

1,3

Comments

Column 2 of A222378

Links

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

Example

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

Crossrefs

Sequence in context: A033453 A284840 A301749 * A147535 A184309 A051944

Adjacent sequences: A222370 A222371 A222372 * A222374 A222375 A222376

Keyword

nonn

Author

R. H. Hardin Feb 17 2013

Status

approved