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Number of (n+1)X(n+1) 0..3 arrays with no 2X2 subblock having its maximum diagonal element less than its minimum antidiagonal element
1

%I #5 Dec 01 2014 11:08:54

%S 230,164800,1497752279,172919373209920,253597772369472323328,

%T 4724687679127024503784365440,1118224116880857883546078105623321344,

%U 3362121790823480902189703776276345356341787648

%N Number of (n+1)X(n+1) 0..3 arrays with no 2X2 subblock having its maximum diagonal element less than its minimum antidiagonal element

%C Diagonal of A251283

%H R. H. Hardin, <a href="/A251275/b251275.txt">Table of n, a(n) for n = 1..9</a>

%e Some solutions for n=2

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 01 2014