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A258963 Number of (n+2) X (5+2) 0..1 arrays with no 3 X 3 subblock diagonal sum 0 and no antidiagonal sum 3 and no row sum 0 or 3 and no column sum 0 or 3. 1

%I #7 Dec 24 2018 07:45:56

%S 676,614,288,340,384,466,552,724,912,1248,1632,2296,3072,4392,5952,

%T 8584,11712,16968,23232,33736,46272,67272,92352,134344,184512,268488,

%U 368832,536776,737472,1073352,1474752,2146504,2949312,4292808,5898432,8585416

%N Number of (n+2) X (5+2) 0..1 arrays with no 3 X 3 subblock diagonal sum 0 and no antidiagonal sum 3 and no row sum 0 or 3 and no column sum 0 or 3.

%H R. H. Hardin, <a href="/A258963/b258963.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-2) - 2*a(n-4) for n>10.

%F Empirical g.f.: 2*x*(338 + 307*x - 870*x^2 - 751*x^3 + 436*x^4 + 337*x^5 - 12*x^6 + 3*x^7 + 12*x^8 + 4*x^9) / ((1 - x)*(1 + x)*(1 - 2*x^2)). - _Colin Barker_, Dec 24 2018

%e Some solutions for n=4:

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

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

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

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

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

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

%Y Column 5 of A258966.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jun 15 2015

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Last modified May 4 17:24 EDT 2024. Contains 372257 sequences. (Running on oeis4.)