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A209681 Number of n X n 0..6 arrays with every element equal to a diagonal or antidiagonal reflection, and new values 0 upwards introduced in row major order.

%I A209681 #10 Jul 22 2025 21:54:02
%S A209681 1,15,1549,11315839,268997909000,250057183645608263,
%T A209681 431066310742284246294717,26767947592293738225917871688575,
%U A209681 3047486118401281699024754722202652309976
%N A209681 Number of n X n 0..6 arrays with every element equal to a diagonal or antidiagonal reflection, and new values 0 upwards introduced in row major order.
%C A209681 Column 5 of A209684
%H A209681 R. H. Hardin, <a href="/A209681/b209681.txt">Table of n, a(n) for n = 1..46</a>
%e A209681 Some.solutions.for.n=3
%e A209681 ..0..0..1....0..1..0....0..1..2....0..0..1....0..1..1....0..1..2....0..1..2
%e A209681 ..1..1..0....0..1..1....1..1..1....0..0..1....1..2..0....1..2..0....1..1..0
%e A209681 ..0..1..1....0..0..0....3..1..0....2..1..1....3..0..1....2..0..1....0..0..0
%K A209681 nonn
%O A209681 1,2
%A A209681 _R. H. Hardin_ Mar 11 2012