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A206320 Number of (n+1) X 2 0..3 arrays with every 2 X 3 or 3 X 2 subblock having exactly three clockwise edge increases. 1
256, 1344, 10504, 83088, 673124, 5432884, 43848120, 353716772, 2853265228, 23015359308, 185649551836, 1497511097624, 12079428217088, 97436737226308, 785957567591456, 6339798686936496, 51138953368767152, 412504036786299552 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Column 1 of A206327.
LINKS
FORMULA
Empirical: a(n) = 9*a(n-1) - 5*a(n-2) - 26*a(n-3) + 42*a(n-4) + 19*a(n-5) + 42*a(n-6) + 14*a(n-7) for n>8.
Empirical g.f.: 4*x*(64 - 240*x - 78*x^2 + 482*x^3 + 511*x^4 + 500*x^5 + 154*x^6 + 8*x^7) / (1 - 9*x + 5*x^2 + 26*x^3 - 42*x^4 - 19*x^5 - 42*x^6 - 14*x^7). - Colin Barker, Jun 15 2018
EXAMPLE
Some solutions for n=4:
..0..0....3..2....1..1....1..1....3..2....3..2....1..3....0..3....2..2....3..1
..1..1....1..1....2..2....3..3....0..1....0..3....2..2....0..0....0..3....0..1
..3..2....3..2....1..0....1..0....3..2....3..0....0..3....3..2....3..2....3..2
..0..3....0..3....0..3....2..1....1..1....1..3....2..1....2..1....0..3....0..0
..1..0....1..0....1..0....1..3....0..2....2..1....1..0....3..2....1..0....3..1
CROSSREFS
Cf. A206327.
Sequence in context: A231943 A206327 A242257 * A237315 A237309 A188865
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 06 2012
STATUS
approved

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Last modified March 28 20:05 EDT 2024. Contains 371254 sequences. (Running on oeis4.)