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Number of nX3 0..1 arrays with every element unequal to 0, 1, 3, 4, 6 or 8 king-move adjacent elements, with upper left element zero.
1

%I #4 Jun 29 2018 07:19:27

%S 3,7,10,21,44,83,168,365,766,1615,3490,7555,16450,36279,80602,180187,

%T 405906,920301,2097902,4807235,11066060,25572903,59300268,137919877,

%U 321585732,751461855,1759215072,4124852047,9684327044,22762103611

%N Number of nX3 0..1 arrays with every element unequal to 0, 1, 3, 4, 6 or 8 king-move adjacent elements, with upper left element zero.

%C Column 3 of A316311.

%H R. H. Hardin, <a href="/A316306/b316306.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 4*a(n-1) -4*a(n-2) +5*a(n-3) -16*a(n-4) +12*a(n-5) -7*a(n-6) +18*a(n-7) -14*a(n-8) +12*a(n-9) +2*a(n-10) +11*a(n-11) -13*a(n-12) -10*a(n-13) -5*a(n-14) -2*a(n-15) +4*a(n-16)

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A316311.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jun 29 2018