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Number of (n+2)X(6+2) 0..1 arrays with no 3x3 subblock diagonal sum 3 and no antidiagonal sum 3 and no row sum 0 and no column sum 0
1

%I #4 Apr 09 2015 14:44:40

%S 12914,12280,16560,18688,47440,72192,155792,255488,600080,869632,

%T 2236176,3351808,8175376,12600576,31831312,46718208,122490640,

%U 182095104,471224592,698647808,1859822352,2698396928,7245722896,10683665664

%N Number of (n+2)X(6+2) 0..1 arrays with no 3x3 subblock diagonal sum 3 and no antidiagonal sum 3 and no row sum 0 and no column sum 0

%C Column 6 of A256748

%H R. H. Hardin, <a href="/A256746/b256746.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = -2*a(n-1) +4*a(n-2) +24*a(n-3) +27*a(n-4) -70*a(n-5) -198*a(n-6) -88*a(n-7) +408*a(n-8) +648*a(n-9) -48*a(n-10) -896*a(n-11) -704*a(n-12) +384*a(n-13) +512*a(n-14) for n>18

%e Some solutions for n=4

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

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

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

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

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

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

%Y Cf. A256748

%K nonn

%O 1,1

%A _R. H. Hardin_, Apr 09 2015