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A209683 Number of n X n 0..8 arrays with every element equal to a diagonal or antidiagonal reflection, and new values 0 upwards introduced in row major order.

%I A209683 #8 Jul 22 2025 21:54:12
%S A209683 1,15,1551,14164693,847881355388,5219870359015849505,
%T A209683 70570762532647014868797563,62256944108221643391817947390337742,
%U A209683 103256072887229091159525820942838733556042886
%N A209683 Number of n X n 0..8 arrays with every element equal to a diagonal or antidiagonal reflection, and new values 0 upwards introduced in row major order.
%C A209683 Column 7 of A209684
%H A209683 R. H. Hardin, <a href="/A209683/b209683.txt">Table of n, a(n) for n = 1..43</a>
%e A209683 Some solutions for n=3
%e A209683 ..0..1..0....0..1..2....0..1..1....0..1..1....0..1..2....0..1..0....0..1..1
%e A209683 ..2..1..1....3..3..1....1..2..0....2..2..1....1..3..3....1..2..2....0..1..1
%e A209683 ..2..2..0....3..3..1....1..0..1....2..2..0....2..3..0....3..2..0....0..0..0
%K A209683 nonn
%O A209683 1,2
%A A209683 _R. H. Hardin_ Mar 11 2012