login
A207045
Number of (n+1) X 4 0..2 arrays with every 2 X 3 or 3 X 2 subblock having exactly one clockwise edge increases.
1
441, 552, 750, 1272, 2094, 3408, 5850, 9792, 15966, 26880, 45024, 73656, 123486, 206976, 339648, 567600, 951390, 1565568, 2610048, 4373160, 7213662, 12005760, 20102688, 33227808, 55236702, 92416512, 153013920, 254174616, 424902750
OFFSET
1,1
COMMENTS
Column 3 of A207050.
LINKS
FORMULA
Empirical: a(n) = 4*a(n-3) +a(n-4) for n>11.
Empirical g.f.: 3*x*(147 + 184*x + 250*x^2 - 164*x^3 - 185*x^4 - 48*x^5 + 4*x^6 + 48*x^7 + 80*x^8 + 24*x^9 + 2*x^10) / (1 - 4*x^3 - x^4). - Colin Barker, Jun 18 2018
EXAMPLE
Some solutions for n=4:
..0..0..1..1....1..0..2..2....2..1..0..0....2..0..0..2....2..2..0..0
..0..0..0..1....1..1..2..2....2..0..0..0....2..0..0..0....2..0..0..0
..1..0..0..0....1..1..1..2....0..0..0..2....2..2..0..0....0..0..0..2
..1..1..0..0....0..1..1..1....0..0..1..1....2..2..2..0....0..0..1..1
..1..1..1..2....0..0..1..1....1..1..1..1....1..2..2..2....1..1..1..1
CROSSREFS
Cf. A207050.
Sequence in context: A124170 A252193 A207650 * A252201 A252194 A057949
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 14 2012
STATUS
approved