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Number of nX3 0..1 arrays with every element unequal to 2, 3, 4 or 6 king-move adjacent elements, with upper left element zero.
2

%I #4 May 07 2018 09:01:10

%S 0,5,4,42,130,464,1722,6378,22939,84079,306987,1119981,4087469,

%T 14922974,54464744,198801521,725648052,2648666277,9667805493,

%U 35288299004,128804934449,470147769118,1716075418498,6263806496746,22863371318814

%N Number of nX3 0..1 arrays with every element unequal to 2, 3, 4 or 6 king-move adjacent elements, with upper left element zero.

%C Column 3 of A304156.

%H R. H. Hardin, <a href="/A304151/b304151.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-1) +4*a(n-2) -14*a(n-4) -35*a(n-5) +11*a(n-6) +41*a(n-7) +53*a(n-8) +3*a(n-9) -116*a(n-10) -148*a(n-11) +62*a(n-12) +213*a(n-13) +137*a(n-14) +57*a(n-15) +18*a(n-16) +6*a(n-17) +2*a(n-18) for n>19

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A304156.

%K nonn

%O 1,2

%A _R. H. Hardin_, May 07 2018