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%I #5 Mar 31 2012 12:37:14
%S 23,529,7891,130165,2113177,34303001,555815721,9009608765,
%T 146090588449,2369000508453,38413524599409,622859701218333,
%U 10099430425592569,163759482495029077,2655320116135400321,43055336278469375613
%N Number of nX3 0..2 arrays avoiding the patterns z z+1 z or z z-1 z in any row or column
%C Column 3 of A207015
%H R. H. Hardin, <a href="/A207010/b207010.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 17*a(n-1) -62*a(n-2) +504*a(n-3) +4150*a(n-4) +5956*a(n-5) +52500*a(n-6) +324172*a(n-7) -312336*a(n-8) -7411552*a(n-9) -17702840*a(n-10) +3602080*a(n-11) +84650816*a(n-12) +197673664*a(n-13) +227286144*a(n-14) +39420416*a(n-15) -347133568*a(n-16) -622917632*a(n-17) -875376640*a(n-18) -427984896*a(n-19) -202702848*a(n-20) +417185792*a(n-21) +142204928*a(n-22) +58327040*a(n-23) -46792704*a(n-24) +1310720*a(n-25)
%e Some solutions for n=4
%e ..0..0..2....2..1..0....2..2..0....1..2..2....1..2..2....2..0..1....2..2..1
%e ..0..0..2....2..1..0....0..0..2....0..0..1....2..1..0....0..0..2....2..0..0
%e ..0..0..0....2..1..1....2..0..0....2..2..0....2..0..1....1..1..2....2..0..0
%e ..1..2..0....0..1..1....1..0..2....1..2..2....2..2..1....1..1..1....2..2..2
%K nonn
%O 1,1
%A _R. H. Hardin_ Feb 14 2012
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