Comments on "A curiosum concerning discrete time convolution" (by E.B. Hall and G.L. Wise)

It is stated that the necessary and sufficient conditions originally considered in the above-named work (see ibid., vol.38, no.6, p.1058-9, 1990) to get an identically zero result when convolving two nonzero absolutely summable sequences is that these sequences have nonoverlapping Fourier spectra, and that there are infinitely many nowhere zero sequences verifying this condition.<
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