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A205939
Number of (n+1) X 4 0..3 arrays with no 2 X 2 subblock having the number of clockwise edge increases equal to the number of counterclockwise edge increases in its adjacent leftward or upward neighbors.
1
12712, 81864, 754704, 6705048, 59081744, 519841120, 4654724592, 41664657416, 370163231264, 3293397673768, 29454711836216, 262833979249240, 2340418899019728, 20866728142257848, 186303761325591116
OFFSET
1,1
COMMENTS
Column 3 of A205944.
LINKS
EXAMPLE
Some solutions for n=4:
..3..2..2..2....1..3..1..0....1..0..1..3....2..0..0..1....3..3..0..1
..3..1..2..2....3..3..2..1....3..3..2..0....3..0..2..0....0..0..3..2
..3..3..0..1....1..0..3..3....0..0..3..3....3..3..0..0....0..0..0..3
..3..3..3..2....2..1..3..2....0..0..1..3....3..3..0..0....3..0..0..1
..2..2..0..3....3..1..1..0....2..3..2..0....2..2..2..1....2..3..3..2
CROSSREFS
Sequence in context: A105655 A124411 A256809 * A278585 A288355 A163573
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 01 2012
STATUS
approved