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 A204435 Symmetric matrix: f(i,j)=((i+j)^2 mod 3), read by (constant) antidiagonals. 15
 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 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, 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}.  In the following guide to related matrices and permanents, Duvwxyz means the matrix remaining after deleting row 1 of the matrix Auvwxyz: Matrix..............Permanent of n-th submatrix A204435=D204439.....A204436 A204437=D204435.....A204438 A204439=D204437.....A204439 A204441=D204447.....A204442 A204443=D204441.....A204444 A204445=D204443.....A204446 A204447=D204445.....A204448 Homer and Goldman mention this as an example of a two-dimensional recurrence. - N. J. A. Sloane, Aug 29 2018 REFERENCES Homer, Steven, and Jerry Goldman. "Doubly-periodic sequences and two-dimensional recurrences." SIAM Journal on Algebraic Discrete Methods 6.3 (1985): 360-370. See page 369. LINKS EXAMPLE Northwest corner: 1 0 1 1 0 1 0 1 1 0 1 1 1 1 0 1 1 0 1 0 1 1 0 1 0 1 1 0 1 1 1 1 0 1 1 0 MATHEMATICA f[i_, j_] := Mod[(i + j)^2, 3]; 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}]]       (* A204435 *) Permanent[m_] :=   With[{a = Array[x, Length[m]]},    Coefficient[Times @@ (m.a), Times @@ a]]; Table[Permanent[m[n]], {n, 1, 22}]   (* A204436 *) CROSSREFS Cf. A204436. Sequence in context: A194661 A285427 A285621 * A267155 A204445 A179184 Adjacent sequences:  A204432 A204433 A204434 * A204436 A204437 A204438 KEYWORD nonn,tabl AUTHOR Clark Kimberling, Jan 15 2012 STATUS approved

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Last modified November 17 14:18 EST 2018. Contains 317276 sequences. (Running on oeis4.)