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Number of nX4 0..1 arrays with every element unequal to 0, 1 or 3 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
1

%I #4 Aug 06 2018 12:11:30

%S 5,7,11,10,14,23,32,55,86,143,226,367,599,967,1581,2574,4220,6868,

%T 11207,18264,29787,48612,79373,129646,211599,345398,563683,919995,

%U 1501558,2451270,4001959,6533101,10664515,17407925,28415437,46383330,75715684

%N Number of nX4 0..1 arrays with every element unequal to 0, 1 or 3 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

%C Column 4 of A317773.

%H R. H. Hardin, <a href="/A317769/b317769.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +2*a(n-4) +6*a(n-7) -a(n-8) -a(n-9) -a(n-10) -7*a(n-11) -7*a(n-12) +2*a(n-13) -a(n-14) for n>23

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A317773.

%K nonn

%O 1,1

%A _R. H. Hardin_, Aug 06 2018