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 A252011 Number of (n+2) X (4+2) 0..3 arrays with every 3 X 3 subblock row and column sum 1 3 6 or 8 and every diagonal and antidiagonal sum not 1 3 6 or 8. 1

%I #8 Dec 01 2018 06:54:42

%S 1618,2002,2170,3814,8482,16994,29954,67714,136002,239874,541762,

%T 1088002,1918978,4334082,8704002,15351810,34672642,69632002,122814466,

%U 277381122,557056002,982515714,2219048962,4456448002,7860125698,17752391682

%N Number of (n+2) X (4+2) 0..3 arrays with every 3 X 3 subblock row and column sum 1 3 6 or 8 and every diagonal and antidiagonal sum not 1 3 6 or 8.

%H R. H. Hardin, <a href="/A252011/b252011.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) + 8*a(n-3) - 8*a(n-4) for n>12.

%F Empirical g.f.: 2*x*(809 + 192*x + 84*x^2 - 5650*x^3 + 798*x^4 + 3584*x^5 - 96*x^6 + 208*x^7 + 96*x^8 + 96*x^9 - 96*x^10 - 32*x^11) / ((1 - x)*(1 - 2*x)*(1 + 2*x + 4*x^2)). - _Colin Barker_, Dec 01 2018

%e Some solutions for n=4:

%e ..2..3..1..2..3..1....1..2..3..1..2..3....1..1..1..1..1..1....2..2..2..2..2..2

%e ..2..2..2..2..2..2....1..1..1..1..1..1....3..1..2..3..1..2....2..3..1..2..0..1

%e ..2..1..0..2..1..3....1..3..2..1..0..2....2..1..3..2..1..3....2..1..0..2..1..0

%e ..2..3..1..2..0..1....1..2..3..1..2..3....1..1..1..1..1..1....2..2..2..2..2..2

%e ..2..2..2..2..2..2....1..1..1..1..1..1....3..1..2..0..1..2....2..3..1..2..0..1

%e ..2..3..3..2..1..3....1..0..2..1..3..2....2..1..3..2..1..0....2..1..0..2..1..3

%Y Column 4 of A252015.

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 12 2014

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Last modified September 7 20:21 EDT 2024. Contains 375749 sequences. (Running on oeis4.)