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 A228655 Number of nX3 binary arrays with top left value 1 and no two ones adjacent horizontally, diagonally or antidiagonally. 1

%I

%S 2,8,34,140,574,2348,9598,39224,160282,654944,2676202,10935332,

%T 44683222,182581508,746051878,3048465200,12456425842,50898577976,

%U 207978216754,849826072316,3472499977390,14189087019740,57978456949582

%N Number of nX3 binary arrays with top left value 1 and no two ones adjacent horizontally, diagonally or antidiagonally.

%C Column 3 of A228660

%H R. H. Hardin, <a href="/A228655/b228655.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 5*a(n-1) -3*a(n-2) -3*a(n-3).

%F Empirical: G.f. -2*x*(-1+x) / ( 1-5*x+3*x^2+3*x^3 ). - _R. J. Mathar_, Aug 29 2013

%e Some solutions for n=4

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Aug 29 2013

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Last modified January 22 04:27 EST 2020. Contains 331133 sequences. (Running on oeis4.)