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A207276 Number of n X 1 0..3 arrays avoiding the patterns z z+1 z or z z-1 z in any row, column, diagonal or antidiagonal. 4
4, 16, 58, 214, 788, 2902, 10686, 39350, 144902, 533586, 1964872, 7235426, 26643664, 98112376, 361288084, 1330403818, 4899066416, 18040275760, 66431340558, 244626139148, 900808977386, 3317130444708, 12214969725478, 44980288801238 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 1 of A207283.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = 3*a(n-1) + 2*a(n-2) + a(n-3) + 3*a(n-4) + a(n-5).

Empirical g.f.: 2*x*(1 + x)*(2 + x^2 + x^3) / (1 - 3*x - 2*x^2 - x^3 - 3*x^4 - x^5). - Colin Barker, Feb 20 2018

EXAMPLE

Some solutions for n=4:

..0....1....1....0....0....2....1....2....0....1....1....2....0....2....1....3

..1....3....0....2....3....0....3....2....2....3....3....3....0....0....1....0

..1....2....0....1....1....1....0....1....2....2....0....3....1....1....0....3

..3....2....0....3....2....2....0....0....1....1....1....0....1....1....3....1

CROSSREFS

Cf. A207283.

Sequence in context: A224128 A123893 A134762 * A047123 A297096 A330791

Adjacent sequences:  A207273 A207274 A207275 * A207277 A207278 A207279

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 16 2012

STATUS

approved

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Last modified September 28 19:16 EDT 2021. Contains 347717 sequences. (Running on oeis4.)