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Number of (n+2)X(n+2) 0..3 arrays with every 3X3 subblock row and column sum equal to 0 3 5 6 or 8 and every 3X3 diagonal and antidiagonal sum not equal to 0 3 5 6 or 8
1

%I #5 Dec 16 2014 19:46:59

%S 2018,5716,10070,63277,1091359,19701604,287805377,24700406029,

%T 1636863026983,40269631420248,15643196598176434,4050536254392615455,

%U 146409505382398682020,266464589627529326041843

%N Number of (n+2)X(n+2) 0..3 arrays with every 3X3 subblock row and column sum equal to 0 3 5 6 or 8 and every 3X3 diagonal and antidiagonal sum not equal to 0 3 5 6 or 8

%C Diagonal of A252334

%H R. H. Hardin, <a href="/A252326/b252326.txt">Table of n, a(n) for n = 1..16</a>

%e Some solutions for n=4

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 16 2014