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A209677 Number of n X n 0..n arrays with every element equal to a diagonal or antidiagonal reflection, and new values 0 upwards introduced in row major order.

%I A209677 #11 Jul 22 2025 21:53:22
%S A209677 1,14,1243,6716352,268997909000,1568091719977974635,
%T A209677 70570762532647014868797563,841333288100321854075145135825724005,
%U A209677 79538689762318826508394939059605661254128283987
%N A209677 Number of n X n 0..n arrays with every element equal to a diagonal or antidiagonal reflection, and new values 0 upwards introduced in row major order.
%C A209677 Diagonal of A209684
%H A209677 R. H. Hardin, <a href="/A209677/b209677.txt">Table of n, a(n) for n = 1..34</a>
%e A209677 Some.solutions.for.n=3
%e A209677 ..0..0..1....0..0..0....0..1..0....0..0..1....0..1..1....0..1..1....0..1..1
%e A209677 ..0..1..2....0..1..1....1..2..1....2..1..0....1..0..0....1..0..2....1..1..2
%e A209677 ..1..2..0....2..1..1....2..1..1....0..2..0....0..0..1....2..2..0....1..2..1
%K A209677 nonn
%O A209677 1,2
%A A209677 _R. H. Hardin_ Mar 11 2012