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 A204551 Symmetric matrix: f(i,j)=floor[(2i+2j+1)/4]-floor[(i+j)/4], by (constant) antidiagonals. 8
 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 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, 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 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,11 COMMENTS For n>=1, the number of occurrences of n is 16n-6.  In the following guide to related matrices and permanents, Duvwxyz represents the matrix remaining after row 1 of the matrix Auvwxyz is deleted: Matrix...............Permanent of n-th submatrix A204551..............A204552 A204553=D204551......A204554 A204560=D204553......A204561 A204562=D204560......A204563 LINKS EXAMPLE Northwest corner: 1 1 1 1 2 2 2 2 3 1 1 1 2 2 2 2 3 3 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 MATHEMATICA f[i_, j_] := Floor[(2 i + 2 j + 1)/4] - Floor[(i + j)/4]; m[n_] := Table[f[i, j], {i, 1, n}, {j, 1, n}] TableForm[m[16]] (* 8x8 principal submatrix *) Flatten[Table[f[i, n + 1 - i],   {n, 1, 14}, {i, 1, n}]]    (* A204551 *) Permanent[m_] :=   With[{a = Array[x, Length[m]]},    Coefficient[Times @@ (m.a), Times @@ a]]; Table[Permanent[m[n]], {n, 1, 15}]  (* A204552 *) CROSSREFS Cf. A204551, A204296. Sequence in context: A121902 A087103 A287091 * A211661 A111972 A073458 Adjacent sequences:  A204548 A204549 A204550 * A204552 A204553 A204554 KEYWORD nonn,tabl AUTHOR Clark Kimberling, Jan 16 2012 STATUS approved

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