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 A113923 A Farey like level n=2 rational function as a coefficient expansion. 2
 12, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 LINKS FORMULA b(n)=coefficient expansion of -3* (-2 + x^2)^2/(49* x^2 (-1 + x^2)), a(n) = 49*b(n) MATHEMATICA k[n_] = -(-1 + 2^(-n))^(-n)* (-2 + 2^(-n))^n *(-1 + 2^n) j[x_, n_] = (x^n - 2)^n/(k[n]*x^n*(x^n - 1)^(n - 1)) (* Farey like function*) f[x_] := 1/(j[x, 2]) /; 0 <= x <= 1/2 f[x_] := j[x, 2] /; 1/2 < x <= 2 ff[x_] = f[Mod[Abs[x], 2]] Plot[f[Mod[Abs[x], 2]], {x, 0, 2}] (*n=2 level*) b = 49*ReplacePart[Table[Coefficient[Series[ -3* (-2 + x^2)^2/(49* x^2 (-1 + x^2)), {x, 0, 30}], x^n], {n, -2, 30}], 3/49, 3] (* removing the zeros*) c = Flatten[Table[If[b[[n]] > 0, b[[n]], {}], {n, 1, Length[b]}]] CROSSREFS Sequence in context: A038328 A126860 A010203 * A129197 A098067 A070604 Adjacent sequences:  A113920 A113921 A113922 * A113924 A113925 A113926 KEYWORD nonn AUTHOR Roger L. Bagula, Jan 30 2006 STATUS approved

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Last modified August 4 16:34 EDT 2020. Contains 336202 sequences. (Running on oeis4.)