A205730 Number of (n+1) X 3 0..2 arrays with every 2 X 2 subblock having the same number of clockwise edge increases as its horizontal neighbors and no 2 X 2 subblock having the same number of counterclockwise edge increases as its vertical neighbors.

369, 978, 3318, 9198, 34674, 97380, 370008, 1053624, 4060848, 11593452, 44691564, 127862298, 493245942, 1412611194, 5445496374, 15610049862, 60135842922, 172528522548, 664117714260, 1906895501304, 7334482622244, 21076547401356

Offset

1,1

Comments

Column 2 of A205736.

Links

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

Formula

Empirical: a(n) = a(n-1) +11*a(n-2) -9*a(n-3) +8*a(n-4) -26*a(n-5) -99*a(n-6) +51*a(n-7) +135*a(n-8) +25*a(n-9) -54*a(n-10) -42*a(n-11) for n>14.

Example

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

Crossrefs

Sequence in context: A294711 A062041 A373764 * A251132 A183351 A275170

Adjacent sequences: A205727 A205728 A205729 * A205731 A205732 A205733

Keyword

nonn

Author

R. H. Hardin, Jan 30 2012

Status

approved