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Number of (n+2) X 9 binary arrays avoiding patterns 001 and 110 in rows, columns and nw-to-se diagonals.
1

%I #8 May 31 2018 08:15:49

%S 888,1568,3652,7238,14338,25576,45156,74150,120170,184864,280724,

%T 410102,592098,829896,1151188,1560118,2095210,2761696,3611428,4650854,

%U 5947906,7510376,9425284,11701894,14449578,17679200,21526004,26002582,31273826

%N Number of (n+2) X 9 binary arrays avoiding patterns 001 and 110 in rows, columns and nw-to-se diagonals.

%C Column 7 of A202447.

%H R. H. Hardin, <a href="/A202446/b202446.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-1) +a(n-2) -11*a(n-3) +6*a(n-4) +14*a(n-5) -14*a(n-6) -6*a(n-7) +11*a(n-8) -a(n-9) -3*a(n-10) +a(n-11) for n>12.

%F Empirical g.f.: 2*x*(444 - 548*x - 970*x^2 + 2241*x^3 + 446*x^4 - 3172*x^5 + 1138*x^6 + 1774*x^7 - 1346*x^8 - 192*x^9 + 416*x^10 - 103*x^11) / ((1 - x)^7*(1 + x)^4). - _Colin Barker_, May 31 2018

%e Some solutions for n=4:

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

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

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

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

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

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

%Y Cf. A202447.

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 19 2011