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A206116
Number of (n+1) X 7 0..3 arrays with every 2 X 3 or 3 X 2 subblock having exactly two counterclockwise and two clockwise edge increases.
1
973388, 3048096, 10792800, 157206240, 1990281312, 24408220320, 373319837280, 4839970998240, 59527064527200, 912767002149600, 11833729090696800, 145543672769004000, 2231715320255772000, 28933467626753676000
OFFSET
1,1
COMMENTS
Column 6 of A206118.
LINKS
FORMULA
Empirical: a(n) = 2445*a(n-3) for n>9.
EXAMPLE
Some solutions for n=4:
..3..2..0..1..3..3..2....3..3..0..3..3..1..2....1..0..2..1..2..2..3
..2..2..0..0..1..3..3....3..2..3..3..0..2..2....0..0..2..2..1..2..2
..1..1..2..0..0..1..3....2..3..3..0..2..2..3....2..2..1..2..2..0..2
..0..1..1..3..0..0..1....3..3..1..2..2..3..2....3..2..2..0..2..2..0
..1..2..1..1..2..0..0....1..1..2..2..3..2..2....2..3..2..2..3..2..0
CROSSREFS
Sequence in context: A178292 A237337 A230030 * A230538 A254089 A254096
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 03 2012
STATUS
approved