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 A282343 A pseudorandom binary sequence with minimum peak to peak distance of the absolute values of its discrete Fourier transform. 1
 1, 0, 1, 1, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 1, 1, 0, 1, 0, 0, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(1) = 1. Each subsequent term is chosen so as to minimize the peak to peak distance of the absolute values of the discrete Fourier transform of the partial sequence. If the peak to peak distance doesn't change with different choices for the next term, then the complement of the previous term is used. The algorithm works on a sequence of 1's and -1's then, as a last step, all -1's are replaced by 0's. This sequence is similar to A282339 where it is considered the variance instead of the peak to peak distance. LINKS MATHEMATICA peaktopeakfourier[x_] := Max[Abs[Fourier[x]]] - Min[Abs[Fourier[x]]]; a = {1}; (*First element*) nmax = 120; (*number of appended elements*) Do[If[peaktopeakfourier[Append[a, 1]] <    peaktopeakfourier[Append[a, -1]], AppendTo[a, 1],   If[peaktopeakfourier[Append[a, 1]] >     peaktopeakfourier[Append[a, -1]], AppendTo[a, -1],    AppendTo[a, -a[[-1]]]]], {j, nmax}]; a = a /. {-1 -> 0}; print[a] CROSSREFS Cf. A280711, A280816, A282339. Sequence in context: A000480 A118251 A209198 * A099076 A282339 A175479 Adjacent sequences:  A282340 A282341 A282342 * A282344 A282345 A282346 KEYWORD nonn,base AUTHOR Andres Cicuttin, Feb 12 2017 STATUS approved

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Last modified August 11 04:03 EDT 2020. Contains 336421 sequences. (Running on oeis4.)