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Number of (n+2) X (6+2) 0..1 arrays with no 3 x 3 subblock diagonal sum 0 and no antidiagonal sum 3 and no row sum 1 and no column sum 1.
1

%I #7 Dec 21 2018 09:05:12

%S 90,95,104,116,134,161,200,257,341,464,644,908,1295,1862,2693,3911,

%T 5696,8312,12146,17765,26000,38069,55757,81680,119672,175352,256955,

%U 376550,551825,808703,1185176,1736924,2545550,3730649,5467496,8012969,11743541

%N Number of (n+2) X (6+2) 0..1 arrays with no 3 x 3 subblock diagonal sum 0 and no antidiagonal sum 3 and no row sum 1 and no column sum 1.

%H R. H. Hardin, <a href="/A257445/b257445.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) - a(n-2) + a(n-3) - a(n-4) for n>5.

%F Empirical g.f.: x*(90 - 85*x + 4*x^2 - 87*x^3 + x^4) / ((1 - x)*(1 - x - x^3)). - _Colin Barker_, Dec 21 2018

%e Some solutions for n=4:

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

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

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

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

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

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

%Y Column 6 of A257447.

%K nonn

%O 1,1

%A _R. H. Hardin_, Apr 23 2015