------------------------------

                    For perfect matchints for a 4 by n strip

                 4       2                4       2 2
[[[-RootOf(1 + _Z  - 3 _Z ) (RootOf(1 + _Z  - 3 _Z )  - 3), 1],

                  4       2
    [RootOf(1 + _Z  - 3 _Z ), 1]]]

                    For perfect matchints for a 6 by n strip

                           2
                      19 %1  - 66
[[[%1, 1], [1, - ---------------------],
                      4        2
                 19 %1  - 95 %1  + 109

                4           2                  4        2
     %1 (4199 %1  - 20665 %1  + 22835)    19 %1  - 95 %1  + 109
    [---------------------------------, - ---------------------]]]
                    2      2                        2
              (19 %1  - 66)                    19 %1  - 66

               6           2       4
%1 := RootOf(_Z  - 1 + 6 _Z  - 5 _Z )

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