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A205738
Number of 3X(n+1) 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.
1
360, 978, 3888, 17532, 80916, 376314, 1756446, 8212662, 38432652, 179925948, 842504430, 3945403368, 18476947170, 86532335682, 405257580870, 1897955537136, 8888775949212, 41629230515718, 194964278279712, 913086294849486
OFFSET
1,1
COMMENTS
Row 2 of A205736.
LINKS
FORMULA
Empirical: a(n) = 6*a(n-1) -2*a(n-2) -21*a(n-3) +a(n-4) +25*a(n-5) +14*a(n-6) -4*a(n-8) -2*a(n-9) for n>13.
EXAMPLE
Some solutions for n=4:
..1..1..2..1..0....0..0..0..2..0....2..1..1..0..1....2..2..1..2..1
..0..2..1..2..1....1..2..0..2..0....0..1..2..0..1....0..2..1..2..0
..0..1..1..1..1....0..0..1..0..1....0..2..1..1..0....1..0..2..1..1
CROSSREFS
Sequence in context: A056502 A056492 A158308 * A112536 A140801 A236059
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 30 2012
STATUS
approved