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%I #8 Feb 21 2019 08:24:47
%S 4,15,50,176,614,2141,7472,26070,90964,317393,1107448,3864117,
%T 13482703,47043939,164146038,572739484,1998406551,6972853897,
%U 24329729820,84891460788,296203869417,1033516580387,3606153167543,12582614458784
%N Number of n X 2 0..1 arrays with no 1 equal to more than two of its horizontal, vertical and antidiagonal neighbors.
%H R. H. Hardin, <a href="/A283276/b283276.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) + a(n-2) + 3*a(n-3) - 2*a(n-4) + a(n-5) - 2*a(n-6) + a(n-7) - a(n-8).
%F Empirical g.f.: x*(4 + 3*x + x^2 - x^3 - x^4 - x^5 - x^7) / (1 - 3*x - x^2 - 3*x^3 + 2*x^4 - x^5 + 2*x^6 - x^7 + x^8). - _Colin Barker_, Feb 21 2019
%e Some solutions for n=4:
%e ..1..0. .1..1. .1..1. .0..1. .1..0. .0..1. .1..1. .0..1. .1..1. .1..1
%e ..1..1. .1..0. .0..1. .0..1. .0..1. .1..0. .0..1. .1..1. .0..1. .0..0
%e ..0..0. .0..1. .0..0. .1..0. .0..1. .0..1. .0..1. .0..0. .1..0. .0..1
%e ..0..0. .0..1. .1..1. .0..0. .0..1. .0..0. .0..0. .1..1. .1..0. .0..0
%Y Column 2 of A283282.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 04 2017
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