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Number of (n+2)X(2+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 14:41:54

%S 393,570,1564,2512,6352,12280,28816,60728,137768,311200,695592,

%T 1606920,3675600,8477144,19719880,45890144,107177032,251576104,

%U 590847248,1391314808,3284435240,7758601632,18359082728,43496258888,103115774544

%N Number of (n+2)X(2+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 2 of A256748

%H R. H. Hardin, <a href="/A256742/b256742.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +6*a(n-2) +5*a(n-3) -19*a(n-4) -34*a(n-5) +8*a(n-6) +52*a(n-7) +24*a(n-8) for n>13

%e Some solutions for n=4

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

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

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

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

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

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

%Y Cf. A256748

%K nonn

%O 1,1

%A _R. H. Hardin_, Apr 09 2015