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Number of nX7 0..1 arrays with every element unequal to 0, 1, 2 or 3 king-move adjacent elements, with upper left element zero.
1

%I #4 Apr 29 2018 11:11:18

%S 64,719,294,406,564,894,1476,2252,3461,5631,9362,15569,26111,43960,

%T 73883,124371,209956,354631,598917,1012022,1710721,2891805,4888812,

%U 8266307,13977941,23636428,39970625,67595175,114312998,193321957,326943993

%N Number of nX7 0..1 arrays with every element unequal to 0, 1, 2 or 3 king-move adjacent elements, with upper left element zero.

%C Column 7 of A303727.

%H R. H. Hardin, <a href="/A303726/b303726.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) -a(n-4) -a(n-5) +a(n-7) -a(n-8) -a(n-9) +2*a(n-10) for n>18

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A303727.

%K nonn

%O 1,1

%A _R. H. Hardin_, Apr 29 2018