%I #5 Mar 31 2012 12:36:30

%S 3,23,106,927,4055,23710,139477,791905,4560098,25954025,148624999,

%T 851071784,4868658595,27861309921,159413524406,912205738931,

%U 5219849087169,29868491830580,170911982112069,977981992958773

%N Number of nX4 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 4,3,0,2,2 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 0's, every 3 is next to 3 2's, every 4 is next to 4 2's

%C Column 4 of A197561

%H R. H. Hardin, <a href="/A197557/b197557.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) +11*a(n-2) +30*a(n-3) +99*a(n-4) +337*a(n-5) +247*a(n-6) -8*a(n-7) +687*a(n-8) -1525*a(n-9) -6711*a(n-10) -9212*a(n-11) -7726*a(n-12) -2004*a(n-13) +3907*a(n-14) +17248*a(n-15) +12376*a(n-16) +3805*a(n-17) +42013*a(n-18) +26907*a(n-19) +7443*a(n-20) +6529*a(n-21) -40829*a(n-22) -23857*a(n-23) -22159*a(n-24) +7851*a(n-25) +1395*a(n-26) -23643*a(n-27) +30926*a(n-28) +1501*a(n-29) -46607*a(n-30) -17463*a(n-31) +3072*a(n-32) +1311*a(n-33) +9717*a(n-34) +10645*a(n-35) +3739*a(n-36) -864*a(n-37) -1824*a(n-38) +234*a(n-39) +558*a(n-40) -422*a(n-41) +94*a(n-42) +118*a(n-43) -72*a(n-44) -16*a(n-45) +5*a(n-46)

%e Some solutions containing all values 0 to 4 for n=5

%e ..0..2..0..0....0..0..2..0....0..0..2..0....0..2..0..0....0..2..0..2

%e ..0..2..0..0....2..2..3..1....0..2..4..2....2..4..2..0....2..4..2..0

%e ..2..4..2..0....0..0..2..0....2..3..2..0....0..2..3..2....0..2..3..2

%e ..0..2..3..1....2..2..4..2....0..1..0..0....0..0..1..0....0..0..1..0

%e ..2..0..2..0....0..0..2..0....0..0..0..0....0..0..0..0....0..0..2..0

%K nonn

%O 1,1

%A _R. H. Hardin_ Oct 16 2011