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 A204437 Symmetric matrix: f(i,j)=((i+j+1)^2 mod 3), by (constant) antidiagonals. 3
 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 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, 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, 0, 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 EXAMPLE Northwest corner: 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 1 0 1 1 0 1 MATHEMATICA f[i_, j_] := Mod[(1 + 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}]]         (* A204437 *) Permanent[m_] :=   With[{a = Array[x, Length[m]]},    Coefficient[Times @@ (m.a), Times @@ a]]; Table[Permanent[m[n]], {n, 1, 22}]   (* A204438 *) CROSSREFS Cf. A204438, A204435. Sequence in context: A226162 A276398 A204549 * A257799 A182067 A196147 Adjacent sequences:  A204434 A204435 A204436 * A204438 A204439 A204440 KEYWORD nonn,tabl AUTHOR Clark Kimberling, Jan 15 2012 STATUS approved

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Last modified December 8 12:55 EST 2016. Contains 278945 sequences.