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%I #8 Dec 18 2018 09:25:44
%S 121,310,1008,3241,9961,30529,94351,292130,902991,2789674,8620990,
%T 26645405,82350302,254503207,786546750,2430856047,7512657571,
%U 23218127711,71756425958,221765794486,685375122700,2118176184897,6546298719088
%N Number of (n+2) X (1+2) 0..1 arrays with no 3 x 3 subblock diagonal sum 0 or 1 and no antidiagonal sum 0 or 1 and no row sum 0 and no column sum 0.
%H R. H. Hardin, <a href="/A254971/b254971.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) + 2*a(n-2) + 3*a(n-3) + 5*a(n-4) - a(n-5) - 6*a(n-6) - 7*a(n-7) + 2*a(n-9) - a(n-10) for n>11.
%F Empirical g.f.: x*(121 + 68*x + 146*x^2 + 242*x^3 - 72*x^4 - 328*x^5 - 356*x^6 - 3*x^7 + 96*x^8 - 45*x^9 - 2*x^10) / ((1 + x)*(1 - 3*x + x^2 - 4*x^3 - x^4 + 2*x^5 + 4*x^6 + 3*x^7 - 3*x^8 + x^9)). - _Colin Barker_, Dec 18 2018
%e Some solutions for n=4:
%e ..0..0..1....1..1..1....1..1..0....0..0..1....1..1..1....0..0..1....0..1..1
%e ..1..1..1....1..1..1....1..1..1....0..1..1....0..1..1....1..1..1....0..1..1
%e ..0..1..1....1..0..1....1..1..1....1..1..1....1..1..1....1..0..1....1..1..1
%e ..1..1..0....1..1..1....1..0..0....1..1..1....1..0..1....1..1..1....1..1..1
%e ..0..1..1....1..1..0....1..1..1....0..1..0....1..1..1....0..1..0....0..0..1
%e ..1..0..0....1..0..1....1..1..1....1..0..0....1..0..0....1..0..0....1..1..1
%Y Column 1 of A254978.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 11 2015
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