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A206746
Number of (n+1) X 3 0..3 arrays with every 2 X 3 or 3 X 2 subblock having an equal number of clockwise and counterclockwise edge increases.
1
1888, 36384, 793152, 18037344, 415429504, 9604042208, 222273709440, 5145902199776, 119144947541120, 2758681735263072, 63875017338121856, 1478977179297444448, 34244608814587421568, 792908424546742896352
OFFSET
1,1
COMMENTS
Column 2 of A206752.
LINKS
FORMULA
Empirical: a(n) = 40*a(n-1) -489*a(n-2) +2516*a(n-3) -5247*a(n-4) +276*a(n-5) +15809*a(n-6) -23256*a(n-7) +11000*a(n-8) +184*a(n-9) -832*a(n-10).
EXAMPLE
Some solutions for n=4:
..1..0..3....1..0..1....2..3..0....0..3..3....1..0..0....1..0..0....1..2..0
..3..1..0....3..2..3....1..2..3....0..1..0....1..0..3....0..0..3....2..2..2
..2..3..1....1..3..2....0..1..2....2..1..2....2..1..0....1..0..3....0..0..2
..1..2..3....2..1..3....0..0..1....2..3..2....0..2..1....0..1..0....2..0..2
..0..1..2....3..2..0....3..0..0....0..3..0....1..3..2....1..3..1....3..1..0
CROSSREFS
Sequence in context: A029564 A235295 A237540 * A106764 A157486 A086476
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 12 2012
STATUS
approved