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Number of n X 1 0..2 arrays with no element equal to a strict majority of its king-move neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.
4

%I #9 Feb 21 2018 11:41:28

%S 0,0,2,4,14,40,120,352,1032,3008,8736,25280,72928,209792,601984,

%T 1723392,4923520,14039040,39961088,113562624,322244096,913131520,

%U 2584180736,7304519680,20624050176,58170228736,163908034560,461421658112

%N Number of n X 1 0..2 arrays with no element equal to a strict majority of its king-move neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.

%C Column 1 of A279327.

%H R. H. Hardin, <a href="/A279322/b279322.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 4*a(n-1) - 8*a(n-3) - 4*a(n-4) for n>5.

%F Empirical g.f.: 2*x^3*(1 - 2*x - x^2) / (1 - 2*x - 2*x^2)^2. - _Colin Barker_, Feb 21 2018

%e All solutions for n=4:

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

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

%e ..2. .1. .0. .1

%e ..2. .0. .0. .2

%Y Cf. A279327.

%K nonn

%O 1,3

%A _R. H. Hardin_, Dec 09 2016