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A204441 Symmetric matrix: f(i,j)=floor[(i+j+2)/4]-floor[(i+j-1)/4], by (constant) antidiagonals. 3
1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1

COMMENTS

A block matrix over {0,1}.  For guides to related matrices and permanents, see A204435 and A204263.

LINKS

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

EXAMPLE

Northwest corner:

1 1 1 0 1 1 1 0

1 1 0 1 1 1 0 1

1 0 1 1 1 0 1 1

0 1 1 1 0 1 1 1

1 1 1 0 1 1 1 0

1 1 0 1 1 1 0 1

1 0 1 1 1 0 1 1

0 1 1 1 0 1 1 1

MATHEMATICA

f[i_, j_] :=

Floor[(i + j + 2)/4] - Floor[(i + j - 1)/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, 14}, {i, 1, n}]]        (* A204441 *)

Permanent[m_] :=

  With[{a = Array[x, Length[m]]},

   Coefficient[Times @@ (m.a), Times @@ a]];

Table[Permanent[m[n]], {n, 1, 22}]    (* A204442 *)

CROSSREFS

Cf. A204442, A204435.

Sequence in context: A082551 A152614 A127507 * A127247 A127244 A144778

Adjacent sequences:  A204438 A204439 A204440 * A204442 A204443 A204444

KEYWORD

nonn,tabl

AUTHOR

Clark Kimberling, Jan 15 2012

STATUS

approved

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Last modified November 29 14:52 EST 2020. Contains 338769 sequences. (Running on oeis4.)