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Number of nX4 0..1 arrays avoiding the patterns 0 1 0 or 1 0 1 in any row, column, diagonal or antidiagonal
1

%I #5 Mar 31 2012 12:37:14

%S 10,100,158,556,1866,5804,18528,59888,191484,612874,1966402,6301118,

%T 20187672,64705162,207369486,664535672,2129687696,6825166670,

%U 21872797724,70096742330,224642588748,719921959060,2307166259316,7393882758084

%N Number of nX4 0..1 arrays avoiding the patterns 0 1 0 or 1 0 1 in any row, column, diagonal or antidiagonal

%C Column 4 of A206987

%H R. H. Hardin, <a href="/A206983/b206983.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 4*a(n-1) -4*a(n-2) +10*a(n-3) -18*a(n-4) +8*a(n-5) -16*a(n-6) -4*a(n-7) -3*a(n-8) +21*a(n-9) +13*a(n-10) -12*a(n-11) for n>13

%e Some solutions for n=4

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Feb 14 2012