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Number of n X 5 0..2 arrays with no element x(i,j) adjacent to value 2-x(i,j) horizontally or antidiagonally.
1

%I #8 Oct 08 2018 10:20:16

%S 48,648,8856,121176,1658232,22692312,310536504,4249585944,58154132088,

%T 795819434328,10890517137336,149033007242136,2039465800159992,

%U 27909392872041432,381930508677741624,5226588558469378584

%N Number of n X 5 0..2 arrays with no element x(i,j) adjacent to value 2-x(i,j) horizontally or antidiagonally.

%H R. H. Hardin, <a href="/A233152/b233152.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 15*a(n-1) - 18*a(n-2).

%F Empirical g.f.: 24*x*(2 - 3*x) / (1 - 15*x + 18*x^2). - _Colin Barker_, Oct 08 2018

%e Some solutions for n=4:

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

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

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

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

%Y Column 5 of A233155.

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 05 2013