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Number of nX3 0..1 arrays with every element equal to 0, 1, 4 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
1

%I #4 Apr 11 2018 12:24:58

%S 3,3,8,7,11,18,29,47,76,123,199,322,521,843,1364,2207,3571,5778,9349,

%T 15127,24476,39603,64079,103682,167761,271443,439204,710647,1149851,

%U 1860498,3010349,4870847,7881196,12752043,20633239,33385282,54018521

%N Number of nX3 0..1 arrays with every element equal to 0, 1, 4 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

%C Column 3 of A302680.

%H R. H. Hardin, <a href="/A302675/b302675.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +a(n-2) for n>5

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A302680.

%K nonn

%O 1,1

%A _R. H. Hardin_, Apr 11 2018