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A281600 Number of n X 3 0..2 arrays with no element equal to more than one of its horizontal, diagonal or antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.

%I A281600 #9 Feb 20 2019 05:30:23
%S A281600 4,29,209,1623,12413,95623,736757,5678559,43771933,337417047,
%T A281600 2601018757,20050333455,154561132461,1191459205767,9184555212821,
%U A281600 70800627012031,545778076046781,4207218532446903,32432024283432101,250007502993994607
%N A281600 Number of n X 3 0..2 arrays with no element equal to more than one of its horizontal, diagonal or antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.
%H A281600 R. H. Hardin, <a href="/A281600/b281600.txt">Table of n, a(n) for n = 1..210</a>
%F A281600 Empirical: a(n) = 7*a(n-1) + 10*a(n-2) - 26*a(n-3) - 64*a(n-4) - 40*a(n-5) for n>6.
%F A281600 Empirical g.f.: x*(4 + x - 34*x^2 - 26*x^3 - 28*x^4 - 48*x^5) / (1 - 7*x - 10*x^2 + 26*x^3 + 64*x^4 + 40*x^5). - _Colin Barker_, Feb 20 2019
%e A281600 Some solutions for n=4:
%e A281600 ..0..1..2. .0..1..2. .0..0..1. .0..1..0. .0..1..1. .0..1..2. .0..1..0
%e A281600 ..2..1..0. .2..1..2. .2..1..2. .0..1..0. .0..2..0. .0..2..0. .0..1..0
%e A281600 ..2..1..2. .2..0..0. .2..0..2. .0..1..2. .2..1..0. .0..2..0. .2..1..2
%e A281600 ..0..0..1. .2..1..1. .2..0..2. .2..1..2. .2..0..2. .1..1..0. .0..0..1
%Y A281600 Column 3 of A281605.
%K A281600 nonn
%O A281600 1,1
%A A281600 _R. H. Hardin_, Jan 25 2017