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A280436 Number of nX4 0..1 arrays with no element equal to more than one of its horizontal and vertical neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.

%I A280436 #6 Jan 04 2017 13:14:01
%S A280436 2,20,42,80,138,232,386,640,1062,1764,2934,4884,8134,13548,22562,
%T A280436 37560,62498,103936,172746,286936,476318,790220,1310222,2171180,
%U A280436 3595918,5952452,9848346,16286240,26920122,44477464,73454354,121259824,200099094
%N A280436 Number of nX4 0..1 arrays with no element equal to more than one of its horizontal and vertical neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.
%C A280436 Column 4 of A280440.
%H A280436 R. H. Hardin, <a href="/A280436/b280436.txt">Table of n, a(n) for n = 1..210</a>
%F A280436 Empirical: a(n) = 4*a(n-1) -4*a(n-2) -2*a(n-3) +4*a(n-4) -a(n-6) for n>7.
%F A280436 Empirical g.f.: 2*x + 2*x^2*(10-19*x-4*x^2+13*x^3+x^5+2*x^4) / ( (x-1)^2*(x^2+x-1)^2 ). - _R. J. Mathar_, Jan 04 2017
%e A280436 Some solutions for n=4
%e A280436 ..0..1..1..0. .0..1..0..1. .0..1..1..0. .0..0..1..0. .0..1..0..1
%e A280436 ..1..0..0..1. .1..0..0..0. .1..0..0..1. .1..0..1..0. .1..0..1..0
%e A280436 ..0..1..1..0. .0..1..0..1. .0..1..1..0. .0..1..0..1. .0..1..0..1
%e A280436 ..1..0..1..0. .1..0..1..0. .0..1..0..1. .1..0..1..0. .1..0..0..1
%Y A280436 Cf. A280440.
%K A280436 nonn
%O A280436 1,1
%A A280436 _R. H. Hardin_, Jan 03 2017