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A207009 Number of n X 2 0..2 arrays avoiding the patterns z z+1 z or z z-1 z in any row or column. 3

%I

%S 9,81,529,3721,25921,180625,1256641,8743849,60855601,423577561,

%T 2948164209,20519130025,142812189025,993971114361,6918041467089,

%U 48149568342121,335120802753025,2332439189580889,16233767034063601

%N Number of n X 2 0..2 arrays avoiding the patterns z z+1 z or z z-1 z in any row or column.

%C Column 2 of A207015.

%H R. H. Hardin, <a href="/A207009/b207009.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 7*a(n-1) -6*a(n-2) +22*a(n-3) +114*a(n-4) +104*a(n-5) -184*a(n-6) -352*a(n-7) -128*a(n-8) -64*a(n-9) +32*a(n-10).

%F a(n) = A207008(n)^2. - _Mark van Hoeij_, May 14 2013

%e Some solutions for n=4

%e ..1..0....2..0....1..2....0..2....0..1....0..1....2..0....2..2....0..2....0..2

%e ..1..1....1..2....2..2....0..0....2..1....2..1....0..2....2..1....0..2....2..2

%e ..0..1....0..2....2..2....0..1....2..2....2..0....1..0....2..1....2..2....0..0

%e ..2..0....2..0....2..2....2..1....0..0....0..2....1..2....0..2....0..2....2..1

%Y Cf. A207008, A207015.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 14 2012

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Last modified February 5 20:57 EST 2023. Contains 360087 sequences. (Running on oeis4.)