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A206409
Number of (n+1) X 4 0..2 arrays with every 2 X 3 or 3 X 2 subblock having an equal number of clockwise and counterclockwise edge increases.
1
2457, 69585, 2073999, 62351943, 1876995285, 56515649709, 1701726564411, 51240524315871, 1542900272261037, 46458185448564093, 1398899935206593883, 42122201449345396239, 1268339366974860798957, 38190899219543171363901
OFFSET
1,1
COMMENTS
Column 3 of A206414.
LINKS
FORMULA
Empirical: a(n) = 47*a(n-1) -608*a(n-2) +3198*a(n-3) -5911*a(n-4) -7789*a(n-5) +44215*a(n-6) -38455*a(n-7) -50916*a(n-8) +86298*a(n-9) +5407*a(n-10) -54221*a(n-11) +10208*a(n-12) +11424*a(n-13) -2506*a(n-14) -502*a(n-15) +112*a(n-16).
EXAMPLE
Some solutions for n=4:
..1..1..1..1....0..1..2..0....2..1..1..1....0..0..1..2....1..2..0..2
..1..0..1..2....1..0..1..2....2..1..1..2....1..0..1..1....1..1..2..2
..1..0..0..1....1..1..2..0....1..1..1..1....0..2..0..0....1..2..2..1
..2..1..0..0....0..1..2..2....1..2..2..1....0..0..1..0....2..0..2..2
..0..2..1..0....2..0..1..1....2..2..1..0....2..2..0..1....2..0..0..2
CROSSREFS
Sequence in context: A043620 A282872 A191383 * A252013 A252105 A252098
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 07 2012
STATUS
approved