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%I #4 Nov 23 2013 16:24:21
%S 16,192,1632,14592,132980,1222708,11215820,102219940,933038584,
%T 8540079344,78067411340,713247261668,6518908174356,59590575250044,
%U 544659989843968,4977988468360184,45498912754793708,415866178060623508
%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 vertically
%C Column 2 of A232431
%H R. H. Hardin, <a href="/A232426/b232426.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 5*a(n-1) +14*a(n-2) +177*a(n-3) +593*a(n-4) -762*a(n-5) -9725*a(n-6) -19491*a(n-7) +50600*a(n-8) -46439*a(n-9) -300305*a(n-10) +356396*a(n-11) +708476*a(n-12) +1239102*a(n-13) -2382756*a(n-14) +350424*a(n-15) +2450976*a(n-16) -5740800*a(n-17) +1144832*a(n-18) -1454080*a(n-19) -884736*a(n-20) +262144*a(n-21)
%e Some solutions for n=5
%e ..1..2..1....1..2..0....2..1..0....0..0..1....1..2..1....1..2..1....0..2..1
%e ..0..2..0....0..2..1....1..0..0....1..0..2....0..0..0....0..1..0....1..1..0
%e ..0..1..0....1..2..1....0..2..1....2..1..1....2..1..1....0..2..2....2..1..1
%e ..1..2..0....1..0..0....0..1..0....0..2..0....2..2..2....1..0..1....2..0..2
%e ..0..2..1....2..1..2....2..2..1....1..2..1....1..1..1....2..0..1....1..0..1
%e ..2..1..0....2..1..0....1..0..0....2..1..0....0..0..0....1..0..2....0..1..2
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 23 2013