login
Number of 3Xn 0..2 arrays x(i,j) with each element horizontally, diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 3, and upper left element zero
1

%I #4 Oct 20 2013 06:57:23

%S 0,2,114,2398,35052,552720,8724560,138661614,2199713318,34899147754,

%T 553614141632,8782488190400,139324085002332,2210222301992486,

%U 35062696826816334,556230414443092114,8823972052874445168

%N Number of 3Xn 0..2 arrays x(i,j) with each element horizontally, diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 3, and upper left element zero

%C Row 3 of A230469

%H R. H. Hardin, <a href="/A230471/b230471.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 14*a(n-1) +28*a(n-2) -48*a(n-3) +1092*a(n-4) +977*a(n-5) +713*a(n-6) -890*a(n-7) -1936*a(n-8) -2762*a(n-9) -712*a(n-10) -1021*a(n-11) -128*a(n-12) -438*a(n-13) -24*a(n-15) +16*a(n-16) for n>17

%e Some solutions for n=3

%e ..0..2..0....0..2..1....0..2..0....0..2..1....0..0..2....0..1..0....0..0..2

%e ..1..1..2....1..1..0....0..1..1....1..1..0....2..1..1....2..0..0....2..1..1

%e ..0..0..0....2..0..2....2..0..2....2..0..0....1..2..0....1..2..1....0..2..1

%K nonn

%O 1,2

%A _R. H. Hardin_, Oct 20 2013