A204425 Infinite matrix: f(i,j)=(2i+j+1 mod 3), by antidiagonals.

1, 2, 0, 0, 1, 2, 1, 2, 0, 1, 2, 0, 1, 2, 0, 0, 1, 2, 0, 1, 2, 1, 2, 0, 1, 2, 0, 1, 2, 0, 1, 2, 0, 1, 2, 0, 0, 1, 2, 0, 1, 2, 0, 1, 2, 1, 2, 0, 1, 2, 0, 1, 2, 0, 1, 2, 0, 1, 2, 0, 1, 2, 0, 1, 2, 0, 0, 1, 2, 0, 1, 2, 0, 1, 2, 0, 1, 2, 1, 2, 0, 1, 2, 0, 1, 2, 0, 1, 2, 0, 1, 2, 0, 1, 2, 0, 1, 2, 0

Offset

1,2

Comments

A block matrix over {0,1,2}. See A204263 for a guide to related matrices and permanents.

Links

Table of n, a(n) for n=1..99.

Example

Northwest corner:
1 2 0 1 2 0
0 1 2 0 1 2
2 0 1 2 0 1
1 2 0 1 2 0
0 1 2 0 1 2
2 0 1 2 0 1

Mathematica

f[i_, j_] := Mod[2 i + 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}]]       (* A204425 *)
Permanent[m_] :=
  With[{a = Array[x, Length[m]]},
   Coefficient[Times @@ (m.a), Times @@ a]];
Table[Permanent[m[n]], {n, 1, 22}]    (* A204426 *)

Crossrefs

Cf. A204426, A204263.

Sequence in context: A210255 A283319 A049321 * A245187 A292598 A079113

Adjacent sequences: A204422 A204423 A204424 * A204426 A204427 A204428

Keyword

nonn,tabl

Author

Clark Kimberling, Jan 15 2012

Status

approved