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A197445 Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,1,1,0,0 for x=0,1,2,3,4 1

%I #5 Mar 31 2012 12:36:29

%S 3,12,81,474,2678,15410,88767,510482,2936714,16895217,97197637,

%T 559175541,3216923150,18506887013,106469709385,612517802024,

%U 3523801014059,20272347435052,116626354899557,670948774602366,3859953085161367

%N Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,1,1,0,0 for x=0,1,2,3,4

%C Every 0 is next to 0 2's, every 1 is next to 1 1's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 0's

%C Column 3 of A197450

%H R. H. Hardin, <a href="/A197445/b197445.txt">Table of n, a(n) for n = 1..200</a>

%F Empirical: a(n) = 2*a(n-1) +12*a(n-2) +45*a(n-3) +61*a(n-4) +20*a(n-5) -129*a(n-6) -324*a(n-7) -344*a(n-8) -166*a(n-9) +61*a(n-10) +268*a(n-11) +360*a(n-12) +307*a(n-13) +240*a(n-14) +92*a(n-15) -97*a(n-16) -142*a(n-17) -120*a(n-18) -92*a(n-19) -32*a(n-20) -4*a(n-22) for n>25

%e Some solutions for n=4

%e ..1..1..0....1..0..0....0..1..1....0..3..0....0..1..1....0..1..1....1..1..0

%e ..0..0..0....1..3..0....3..0..0....0..0..0....0..3..0....0..0..0....0..0..0

%e ..0..3..1....0..0..1....0..0..0....0..0..3....0..0..0....3..0..1....0..0..0

%e ..0..0..1....0..0..1....0..1..1....0..0..0....0..0..0....0..0..1....0..3..0

%K nonn

%O 1,1

%A _R. H. Hardin_ Oct 15 2011

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Last modified March 28 13:42 EDT 2024. Contains 371254 sequences. (Running on oeis4.)