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A204431
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Symmetric matrix: f(i,j)=(2i+j+1 mod 3), by antidiagonals.
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3
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2, 1, 1, 0, 0, 0, 2, 2, 2, 2, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1
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OFFSET
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1,1
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COMMENTS
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A block matrix over {0,1,2}. See A204263 for a guide to related matrices and permanents.
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LINKS
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EXAMPLE
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Northwest corner:
2 1 0 2 1 0
1 0 2 1 0 2
0 2 1 0 2 1
2 1 0 2 1 0
1 0 2 1 0 2
0 2 1 0 2 1
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MATHEMATICA
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f[i_, j_] := Mod[2 i + 2 j + 1, 3];
m[n_] := Table[f[i, j], {i, 1, n}, {j, 1, n}]
TableForm[m[8]] (* 8x8 principal submatrix *)
Flatten[Table[f[i, n + 1 - i],
{n, 1, 14}, {i, 1, n}]] (* A204431 *)
Permanent[m_] :=
With[{a = Array[x, Length[m]]},
Coefficient[Times @@ (m.a), Times @@ a]];
Table[Permanent[m[n]], {n, 1, 22}] (* A204432 *)
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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