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A209682 Number of n X n 0..7 arrays with every element equal to a diagonal or antidiagonal reflection, and new values 0 upwards introduced in row major order.

%I A209682 #8 Jul 22 2025 21:54:07
%S A209682 1,15,1551,13575355,584728215424,1568091719977974635,
%T A209682 8230385298024619110939311,2126394147054521999411737472214659,
%U A209682 1020701618427502395624813185662022237910866
%N A209682 Number of n X n 0..7 arrays with every element equal to a diagonal or antidiagonal reflection, and new values 0 upwards introduced in row major order.
%C A209682 Column 6 of A209684
%H A209682 R. H. Hardin, <a href="/A209682/b209682.txt">Table of n, a(n) for n = 1..44</a>
%e A209682 Some solutions for n=3
%e A209682 ..0..0..1....0..0..1....0..0..0....0..1..0....0..1..0....0..1..0....0..0..0
%e A209682 ..2..0..0....0..1..1....0..1..2....2..1..1....1..0..2....2..1..1....1..1..0
%e A209682 ..2..2..1....1..1..1....1..2..1....0..2..1....2..2..0....3..2..1....2..1..1
%K A209682 nonn
%O A209682 1,2
%A A209682 _R. H. Hardin_ Mar 11 2012