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A209585 Number of n X n 0..n arrays with every element equal to a diagonal or antidiagonal reflection.

%I A209585 #9 Jul 22 2025 21:49:44
%S A209585 2,81,28672,791015625,191221621088256,7860041410116536427241,
%T A209585 2836619246897071128576000000000,
%U A209585 304913968803300753908857213381006097576481
%N A209585 Number of n X n 0..n arrays with every element equal to a diagonal or antidiagonal reflection.
%C A209585 Diagonal of A209593
%H A209585 R. H. Hardin, <a href="/A209585/b209585.txt">Table of n, a(n) for n = 1..10</a>
%F A209585 a(n) = (n+1) ^ (2n-(n modulo 2)) * ((n+1)*(2n+1)) ^ ((n*n-2n+(n modulo 2))/4)
%e A209585 Some solutions for n=3
%e A209585 ..0..0..1....3..0..2....2..0..1....0..3..0....2..0..0....3..3..3....0..2..2
%e A209585 ..0..1..1....1..0..0....0..1..3....2..3..3....2..3..0....2..1..3....2..1..2
%e A209585 ..3..1..2....0..1..1....1..3..3....3..2..2....2..2..3....0..2..0....0..2..3
%K A209585 nonn
%O A209585 1,1
%A A209585 _R. H. Hardin_ Mar 10 2012