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%I #5 Mar 31 2012 12:36:29
%S 1,8,44,221,1175,5982,30940,160438,828709,4285218,22165292,114628225,
%T 592784354,3065621155,15854191220,81990622115,424018125103,
%U 2192835511699,11340373874625,58647355280660,303298041583255,1568522750375630
%N Number of nX4 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 4,3,2,1,0 for x=0,1,2,3,4
%C Every 0 is next to 0 4's, every 1 is next to 1 3's, every 2 is next to 2 2's, every 3 is next to 3 1's, every 4 is next to 4 0's
%C Column 4 of A197217
%H R. H. Hardin, <a href="/A197213/b197213.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) +4*a(n-2) +36*a(n-3) +23*a(n-4) -19*a(n-5) -278*a(n-6) -219*a(n-7) -224*a(n-8) +504*a(n-9) +774*a(n-10) -707*a(n-11) -3046*a(n-12) -372*a(n-13) +3206*a(n-14) +2421*a(n-15) -1229*a(n-16) -2776*a(n-17) +652*a(n-18) +3427*a(n-19) +377*a(n-20) -3956*a(n-21) -2455*a(n-22) +2524*a(n-23) +3446*a(n-24) +272*a(n-25) -1845*a(n-26) -1309*a(n-27) -17*a(n-28) +555*a(n-29) +412*a(n-30) +114*a(n-31) -27*a(n-32) -35*a(n-33) -13*a(n-34) -2*a(n-35)
%e Some solutions for n=5
%e ..0..2..2..0....0..0..0..1....2..2..2..0....1..3..1..0....0..0..1..0
%e ..0..2..2..0....0..0..1..3....2..0..2..2....0..1..0..0....0..1..3..1
%e ..0..0..0..0....0..1..0..1....2..0..0..2....0..1..0..0....1..1..3..1
%e ..0..1..0..0....0..3..1..0....2..0..0..2....1..3..2..2....3..1..1..0
%e ..1..3..1..0....0..1..0..0....2..2..2..2....0..1..2..2....1..0..0..0
%K nonn
%O 1,2
%A _R. H. Hardin_ Oct 11 2011
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