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A204545 Symmetric matrix: f(i,j)=floor[(i+j+3)/4]-floor[(i+j+1)/4], by (constant) antidiagonals. 3
1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 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, 0, 0, 0, 0, 0, 0, 0, 0, 0, 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, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1

COMMENTS

A block matrix over {0,1}.  For a guide to related matrices and permanents, see A204269 and A204453.

LINKS

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

EXAMPLE

Northwest corner:

1 0 0 1 1 0 0 1

0 0 1 1 0 0 1 1

0 1 1 0 0 1 1 0

1 1 0 0 1 1 0 0

1 0 0 1 1 0 0 1

0 0 1 1 0 0 1 1

0 1 1 0 0 1 1 0

1 1 0 0 1 1 0 0

MATHEMATICA

f[i_, j_] := Floor[(i + j + 3)/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}]]     (* A204545 *)

Permanent[m_] :=

  With[{a = Array[x, Length[m]]},

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

Table[Permanent[m[n]], {n, 1, 22}]      (* A204546 *)

CROSSREFS

Cf. A204546, A204296.

Sequence in context: A333818 A111412 A080111 * A185116 A014034 A014059

Adjacent sequences:  A204542 A204543 A204544 * A204546 A204547 A204548

KEYWORD

nonn,tabl

AUTHOR

Clark Kimberling, Jan 16 2012

STATUS

approved

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Last modified October 6 14:09 EDT 2022. Contains 357264 sequences. (Running on oeis4.)