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A208491
Number of (n+1) X 8 0..3 arrays with the number of clockwise edge increases in every 2 X 2 subblock equal to the number of counterclockwise edge increases:
1
113880744, 222232271912, 449271828443912, 920635760474340792, 1897470416545860341536, 3920972889443714995894776, 8112174131718066295245481744, 16792956299828228584347524939848
OFFSET
1,1
COMMENTS
Column 7 of A208492.
LINKS
EXAMPLE
Some solutions for n=4:
..0..3..1..2..1..1..1..2....0..0..3..0..1..1..2..0....2..0..3..2..0..2..3..2
..2..0..2..2..1..3..3..0....2..2..1..2..3..3..0..0....3..1..0..3..2..0..1..3
..0..1..3..3..2..0..3..3....2..3..2..0..1..3..3..3....0..3..2..0..3..1..1..1
..3..0..1..3..2..2..0..3....3..1..3..1..3..3..3..1....0..3..2..0..3..3..1..2
..0..2..3..2..3..3..1..0....3..1..3..3..3..1..1..1....1..0..3..1..0..3..3..0
CROSSREFS
Sequence in context: A378059 A281448 A171571 * A205169 A112018 A216010
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 27 2012
STATUS
approved