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A206198
Number of (n+1) X (n+1) 0..3 arrays with every 2 X 3 or 3 X 2 subblock having exactly one clockwise edge increases.
0
256, 1060, 5136, 32920, 118936, 484704, 3270240, 11893600, 48470400, 327024000, 1189360000, 4847040000, 32702400000, 118936000000, 484704000000, 3270240000000, 11893600000000, 48470400000000, 327024000000000
OFFSET
1,1
COMMENTS
Diagonal of A206206.
FORMULA
Conjectures from Colin Barker, Jan 18 2018: (Start)
G.f.: 4*x*(64 + 265*x + 1284*x^2 + 1830*x^3 + 3234*x^4 - 7224*x^5 - 5440*x^6) / (1 - 100*x^3).
a(n) = 100*a(n-3) for n>7.
(End)
EXAMPLE
Some solutions for n=4
..3..3..2..0..0....2..3..3..2..2....2..2..2..1..0....0..1..1..2..2
..3..3..3..0..0....2..3..3..3..1....3..2..2..2..0....0..1..1..1..2
..0..3..3..3..0....2..2..3..3..3....1..1..2..2..2....0..0..1..1..1
..0..0..3..3..3....2..2..2..3..3....1..1..1..2..2....0..0..0..1..1
..0..0..0..3..3....1..2..2..2..2....2..1..1..1..1....1..0..0..0..0
CROSSREFS
Sequence in context: A045034 A236911 A236904 * A237218 A237212 A237694
KEYWORD
nonn
AUTHOR
R. H. Hardin Feb 04 2012
STATUS
approved