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%I #5 Mar 31 2012 12:36:25
%S 4,20,58,290,1217,5110,21969,93666,399920,1714601,7351903,31469992,
%T 134862960,577985643,2477090793,10617586380,45512098214,195087643326,
%U 836266725394,3584843949857,15367390560222,65877090945921
%N Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,0,1,2,4 for x=0,1,2,3,4
%C Every 0 is next to 0 3's, every 1 is next to 1 0's, every 2 is next to 2 1's, every 3 is next to 3 2's, every 4 is next to 4 4's
%C Column 3 of A196218
%H R. H. Hardin, <a href="/A196213/b196213.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = 4*a(n-1) +3*a(n-2) -2*a(n-3) +11*a(n-4) -62*a(n-5) -156*a(n-6) -641*a(n-7) -1661*a(n-8) -89*a(n-9) +1488*a(n-10) +10023*a(n-11) +43316*a(n-12) +46311*a(n-13) +45550*a(n-14) +21396*a(n-15) -79295*a(n-16) -76219*a(n-17) -105192*a(n-18) -56481*a(n-19) +54675*a(n-20) +38374*a(n-21) +65404*a(n-22) +5601*a(n-23) -13298*a(n-24) -5976*a(n-25) -4115*a(n-26) -1642*a(n-27) -2966*a(n-28) -1951*a(n-29) +693*a(n-30) +657*a(n-31) +83*a(n-32) +199*a(n-33) +48*a(n-34) -16*a(n-35) -3*a(n-36)
%e Some solutions for n=4
%e ..1..0..0....1..1..0....0..0..1....1..1..0....1..0..0....0..0..0....0..0..1
%e ..1..2..1....0..1..1....1..1..1....0..1..2....2..2..1....1..1..1....1..1..2
%e ..0..2..1....0..2..1....1..1..0....0..1..1....1..1..2....2..2..1....1..1..2
%e ..1..1..0....0..0..0....0..2..1....1..1..0....0..0..0....1..0..0....0..0..1
%K nonn
%O 1,1
%A _R. H. Hardin_ Sep 29 2011
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