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A204255
Symmetric matrix given by f(i,j)=1+[(i+j) mod 4].
2
3, 4, 4, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4
OFFSET
1,1
EXAMPLE
Northwest corner:
3 4 1 2 3 4 1 2
4 1 2 3 4 1 2 3
1 2 3 4 1 2 3 4
2 3 4 1 2 3 4 1
3 4 1 2 3 4 1 2
4 1 2 3 4 1 2 3
MATHEMATICA
f[i_, j_] := 1 + Mod[i + j, 4];
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, 12}, {i, 1, n}]] (* A204255 *)
Permanent[m_] :=
With[{a = Array[x, Length[m]]},
Coefficient[Times @@ (m.a), Times @@ a]];
Table[Permanent[m[n]], {n, 1, 20}] (* A204256 *)
CROSSREFS
Cf. A204256.
Sequence in context: A057279 A350908 A054733 * A283753 A120649 A001009
KEYWORD
nonn,tabl
AUTHOR
Clark Kimberling, Jan 14 2012
STATUS
approved