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%I #8 Apr 28 2021 01:22:24
%S 120,20691,1400413,75035643,3583403667,159377253183,6749642728251,
%T 275739382892979,10957241965280031,425954258229381831,
%U 16265054107660003947,611918047133484899067,22734198484723715670855
%N Number of defective 3-colorings of an n X 7 0..2 array connected horizontally and antidiagonally with exactly two mistakes, and colors introduced in row-major 0..2 order.
%C Column 7 of A229694.
%H R. H. Hardin, <a href="/A229693/b229693.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 126*a(n-1) - 6345*a(n-2) + 165456*a(n-3) - 2474469*a(n-4) + 22918302*a(n-5) - 138045627*a(n-6) + 554666940*a(n-7) - 1494608922*a(n-8) + 2659094568*a(n-9) - 2986698420*a(n-10) + 1913187600*a(n-11) - 531441000*a(n-12) for n > 14.
%e Some solutions for n=3:
%e 0 0 1 2 1 2 1 0 0 1 0 1 2 1 0 0 1 0 1 2 0
%e 1 0 1 2 1 2 2 1 2 1 0 1 0 2 1 0 2 0 2 1 2
%e 1 2 1 2 1 0 2 1 2 0 2 1 0 2 2 1 2 1 0 1 0
%K nonn
%O 1,1
%A _R. H. Hardin_, Sep 27 2013