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Number of n X n 0..2 arrays with every element equal to a diagonal or antidiagonal reflection
1

%I #6 Dec 18 2015 18:18:04

%S 3,81,3645,1476225,996451875,6053445140625,61291132048828125,

%T 5585154407949462890625,848245325707324676513671875,

%U 1159445329576199417209625244140625

%N Number of n X n 0..2 arrays with every element equal to a diagonal or antidiagonal reflection

%C Column 2 of A209593

%H R. H. Hardin, <a href="/A209587/b209587.txt">Table of n, a(n) for n = 1..30</a>

%F a(n) = 3 ^ (2*n-(n modulo 2)) * 15 ^ ((n*n-2*n+(n modulo 2))/4)

%e Some solutions for n=3

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Mar 10 2012