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A189258 Number of n X 3 binary arrays without the pattern 0 0 1 diagonally, antidiagonally or horizontally. 1
7, 49, 280, 1600, 8985, 50397, 282332, 1581428, 8857677, 49611209, 277868792, 1556321080, 8716833601, 48822302485, 273449899316, 1531571519964, 8578212427349, 48045897623297, 269101318957392, 1507215463960672 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A189264.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..200

FORMULA

Empirical: a(n) = 6*a(n-1) -2*a(n-2) +a(n-4) -50*a(n-5) -6*a(n-6) +140*a(n-7) -56*a(n-8).

Empirical g.f.: x*(7 + 7*x + 18*x^3 - 62*x^4 - 12*x^5 + 132*x^6 - 56*x^7) / (1 - 6*x + 2*x^2 - x^4 + 50*x^5 + 6*x^6 - 140*x^7 + 56*x^8). - Colin Barker, May 01 2018

EXAMPLE

Some solutions for 4 X 3:

..1..1..1....0..1..0....1..1..0....0..1..1....1..1..1....0..1..0....1..1..0

..0..0..0....1..1..0....0..0..0....0..1..1....1..0..1....0..1..0....1..1..1

..0..0..0....1..1..1....0..1..1....0..1..1....0..0..0....1..1..1....0..1..1

..0..1..0....0..1..0....1..0..0....1..1..1....1..0..0....1..1..1....1..0..1

CROSSREFS

Cf. A189264.

Sequence in context: A224131 A218266 A213295 * A188748 A188986 A146884

Adjacent sequences:  A189255 A189256 A189257 * A189259 A189260 A189261

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 19 2011

STATUS

approved

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Last modified August 21 02:08 EDT 2018. Contains 313930 sequences. (Running on oeis4.)