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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 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

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: A260180 A057279 A054733 * A283753 A120649 A001009

Adjacent sequences:  A204252 A204253 A204254 * A204256 A204257 A204258

KEYWORD

nonn,tabl

AUTHOR

Clark Kimberling, Jan 14 2012

STATUS

approved

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Last modified February 25 18:44 EST 2018. Contains 299655 sequences. (Running on oeis4.)