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%I #8 Oct 06 2018 03:53:04
%S 10,34,194,1034,4986,24498,122994,613658,3048362,15169602,75553058,
%T 376118570,1872104666,9319393234,46393400018,230946825274,
%U 1149651799818,5722999066210,28489256322434,141820122223178,705983637088826
%N Number of (n+1) X (2+1) 0..2 arrays with every element next to itself plus and minus one within the range 0..2 horizontally or antidiagonally.
%H R. H. Hardin, <a href="/A232902/b232902.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 4*a(n-1) - a(n-2) + 26*a(n-3) + 16*a(n-4).
%F Empirical g.f.: 2*x*(5 - 3*x + 34*x^2 + 16*x^3) / (1 - 4*x + x^2 - 26*x^3 - 16*x^4). - _Colin Barker_, Oct 06 2018
%e Some solutions for n=5:
%e ..0..1..2....0..1..2....2..1..2....2..1..2....2..1..0....2..1..2....0..1..2
%e ..0..1..0....0..1..2....0..1..2....0..1..2....2..1..0....0..1..0....0..1..0
%e ..2..1..2....2..0..1....0..1..2....0..1..2....0..2..1....2..1..2....0..0..1
%e ..0..2..1....1..2..1....0..1..2....2..1..2....1..0..0....0..0..1....1..2..1
%e ..1..0..0....1..0..0....0..1..0....0..1..2....2..1..0....1..2..0....1..0..0
%e ..0..1..2....0..1..2....2..1..2....0..1..0....0..1..2....2..1..0....0..1..2
%Y Column 2 of A232908.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 02 2013
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