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Number of nX3 0..1 arrays with every element unequal to 2, 3, 5, 6 or 7 king-move adjacent elements, with upper left element zero.
2

%I #4 May 27 2018 17:34:24

%S 0,4,8,15,31,92,264,784,2378,7342,22596,69617,214983,664217,2052307,

%T 6342935,19606074,60603932,187335711,579091828,1790098137,5533594957,

%U 17105617402,52877461311,163456660240,505283076436,1561949355656

%N Number of nX3 0..1 arrays with every element unequal to 2, 3, 5, 6 or 7 king-move adjacent elements, with upper left element zero.

%C Column 3 of A305223.

%H R. H. Hardin, <a href="/A305218/b305218.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) +5*a(n-2) -12*a(n-4) -15*a(n-5) +3*a(n-6) +30*a(n-7) +14*a(n-8) -40*a(n-9) -44*a(n-10) +23*a(n-11) +66*a(n-12) +22*a(n-13) -15*a(n-14) -6*a(n-15) for n>18

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A305223.

%K nonn

%O 1,2

%A _R. H. Hardin_, May 27 2018