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Number of nX3 0..1 arrays with every element unequal to 1, 2, 3, 5 or 6 king-move adjacent elements, with upper left element zero.
1

%I #4 May 17 2018 09:51:37

%S 1,16,56,178,669,2615,9573,35581,133149,495719,1845526,6880247,

%T 25634622,95503501,355868278,1325975629,4940513437,18408548266,

%U 68590644744,255569164599,952255335447,3548119872982,13220347086909,49259228193957

%N Number of nX3 0..1 arrays with every element unequal to 1, 2, 3, 5 or 6 king-move adjacent elements, with upper left element zero.

%C Column 3 of A304697.

%H R. H. Hardin, <a href="/A304692/b304692.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-1) +4*a(n-2) +7*a(n-3) -28*a(n-4) -63*a(n-5) -22*a(n-6) +66*a(n-7) +200*a(n-8) +120*a(n-9) -46*a(n-10) -245*a(n-11) -185*a(n-12) -23*a(n-13) +95*a(n-14) +162*a(n-15) +71*a(n-16) -2*a(n-17) -20*a(n-18) -8*a(n-19) for n>21

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A304697.

%K nonn

%O 1,2

%A _R. H. Hardin_, May 17 2018