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Number of (n+2)X7 0..2 arrays with no 3X3 subblock having three equal diagonal elements or three equal antidiagonal elements, and new values 0..2 introduced in row major order
1

%I #5 Mar 31 2012 12:37:03

%S 537665796,465761252736,387664140116880,323760110018338584,

%T 270709468240858645320,226195161314062528733400,

%U 189028841218044281822571840,157967089903037319532707782016

%N Number of (n+2)X7 0..2 arrays with no 3X3 subblock having three equal diagonal elements or three equal antidiagonal elements, and new values 0..2 introduced in row major order

%C Column 5 of A204782

%H R. H. Hardin, <a href="/A204779/b204779.txt">Table of n, a(n) for n = 1..13</a>

%e Some solutions for n=3

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Jan 19 2012