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 A303685 Number of nX3 0..1 arrays with every element unequal to 2, 3 or 4 king-move adjacent elements, with upper left element zero. 1

%I

%S 0,5,2,20,27,108,191,599,1261,3503,8019,20956,49932,126833,308197,

%T 772321,1894368,4716189,11620491,28839210,71214717,176468284,

%U 436228102,1080165740,2671530008,6612751510,16359100711,40486188269,100169626090

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

%C Column 3 of A303690.

%H R. H. Hardin, <a href="/A303685/b303685.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +6*a(n-2) -3*a(n-3) -9*a(n-4) +7*a(n-5) +3*a(n-6) -20*a(n-7) -3*a(n-8) +12*a(n-9) -12*a(n-11) -3*a(n-12) +2*a(n-13) -5*a(n-14) +a(n-15) +2*a(n-16) for n>18

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A303690.

%K nonn

%O 1,2

%A _R. H. Hardin_, Apr 28 2018

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Last modified December 5 14:49 EST 2021. Contains 349557 sequences. (Running on oeis4.)