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%I #7 Jan 09 2019 11:50:24
%S 5,50,481,4659,45361,440405,4281953,41605113,404371841,3929676961,
%T 38190819553,371149900881,3606990493057,35054056081937,
%U 340669003487777,3310750747302897,32175148917943745,312690400948679185
%N Number of n X 3 integer arrays with each element equal to the number of horizontal and antidiagonal neighbors less than itself.
%H R. H. Hardin, <a href="/A266028/b266028.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 5*a(n-1) + 46*a(n-2) + 6*a(n-3) - 72*a(n-4).
%F Empirical g.f.: x*(1 + 4*x)*(5 + 5*x - 19*x^2) / (1 - 5*x - 46*x^2 - 6*x^3 + 72*x^4). - _Colin Barker_, Jan 09 2019
%e Some solutions for n=4:
%e ..0..0..1....0..0..0....0..0..1....0..1..2....1..0..2....0..0..0....0..0..2
%e ..0..1..1....1..1..2....1..1..0....2..0..0....0..0..0....2..1..1....1..1..0
%e ..1..0..0....2..0..2....1..0..2....0..0..2....0..0..1....2..0..2....2..0..0
%e ..2..0..0....2..0..0....2..0..0....0..0..1....1..3..0....2..1..0....0..0..0
%Y Column 3 of A266033.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 20 2015
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