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 A204175 Symmetric matrix based on f(i,j)=(1 if max(i,j) is even, and 0 otherwise), by antidiagonals. 2
 0, 1, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1 COMMENTS A204175 represents the matrix M given by f(i,j)=(1 if max(i,j) is even, and 0 otherwise) for i>=1 and j>=1.  See A204176 for characteristic polynomials of principal submatrices of M, with interlacing zeros.  See A204016 for a guide to other choices of M. LINKS EXAMPLE Northwest corner: 0 1 0 1 0 1 0 1 1 1 0 1 0 1 0 1 0 0 0 1 0 1 0 1 1 1 1 1 0 1 0 1 0 0 0 0 0 1 0 1 1 1 1 1 1 1 0 1 MATHEMATICA f[i_, j_] := If[Mod[Max[i, j], 2] == 0, 1, 0] 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, 15}, {i, 1, n}]]  (* A204175 *) p[n_] := CharacteristicPolynomial[m[n], x]; c[n_] := CoefficientList[p[n], x] TableForm[Flatten[Table[p[n], {n, 1, 10}]]] Table[c[n], {n, 1, 12}] Flatten[%]                 (* A204176 *) TableForm[Table[c[n], {n, 1, 10}]] CROSSREFS Cf. A204176, A204016, A202453. Sequence in context: A131929 A100821 A139689 * A285255 A324823 A284912 Adjacent sequences:  A204172 A204173 A204174 * A204176 A204177 A204178 KEYWORD nonn,tabl AUTHOR Clark Kimberling, Jan 12 2012 STATUS approved

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Last modified December 6 14:47 EST 2019. Contains 329806 sequences. (Running on oeis4.)