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https://fzp9h5ycrt34.devv.app/ helps to visualize fourier and octave math related to Laegna, based on https://github.com/tambetvali/FrequencyCalculator/blob/main/..., based on https://github.com/tambetvali/FrequencyCalculator/blob/main/... itself. Here, one can see how mathematics, octaves, higher and lower order octaves map with integrals, differentials, fourier and even gauss.