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A204560 Symmetric matrix: f(i,j)=floor[(2i+2j+4)/4]-floor[(i+j+2)/4], by (constant) antidiagonals. 3
1, 1, 1, 2, 2, 2, 2, 2, 2, 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, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

For n>=2, the number of occurrences of n is 16n-14.  For a guide to related sequences and permanents, see A204551.

Northwest corner:

1 1 2 2 2 2 3 3 3

1 2 2 2 2 3 3 3 3

2 2 2 2 3 3 3 3 4

2 2 2 3 3 3 3 4 4

2 3 3 3 3 4 4 4 4

3 3 3 3 4 4 4 4 5

3 3 3 4 4 4 4 5 5

f[i_, j_] := Floor[(2 i + 2 j + 4)/4] - Floor[(i + j + 2)/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}]]     (* A204560 *)

Permanent[m_] :=

  With[{a = Array[x, Length[m]]},

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

Table[Permanent[m[n]], {n, 1, 15}]  (* A204561 *)

Cf. A204561, A204551.

tabl

LINKS

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

CROSSREFS

Sequence in context: A176170 A062153 A217693 * A135661 A082998 A076620

Adjacent sequences:  A204557 A204558 A204559 * A204561 A204562 A204563

KEYWORD

nonn,tabl

AUTHOR

Clark Kimberling, Jan 16 2012

STATUS

approved

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Last modified December 16 06:18 EST 2019. Contains 330016 sequences. (Running on oeis4.)