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Number of n X 2 0..1 arrays with no 1 adjacent to 4 king-move neighboring 1s.
1

%I #8 Feb 26 2019 08:20:57

%S 4,16,58,216,808,3016,11264,42080,157192,587200,2193552,8194256,

%T 30610528,114348992,427163264,1595715392,5960970560,22267862080,

%U 83184051328,310743185408,1160815393920,4336353754624,16198927050240,60512876123648

%N Number of n X 2 0..1 arrays with no 1 adjacent to 4 king-move neighboring 1s.

%H R. H. Hardin, <a href="/A297096/b297096.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 4*a(n-1) - 2*a(n-2) + 6*a(n-3) - 8*a(n-4) - 4*a(n-6).

%F Empirical g.f.: 2*x*(2 + x^2 - 4*x^3 - 2*x^4 - 2*x^5) / (1 - 4*x + 2*x^2 - 6*x^3 + 8*x^4 + 4*x^6). - _Colin Barker_, Feb 26 2019

%e Some solutions for n=7:

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

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

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

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

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

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

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

%Y Column 2 of A297102.

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 25 2017