Correction to a Theorem of Schoenberg
نویسندگان
چکیده
A well–known theorem of Schoenberg states that if f(z) generates a PFr sequence then 1/f(−z) generates a PFr sequence. We give two counterexamples which show that this is not true, and give a correct version of the theorem. In the infinite limit the result is sound: if f(z) generates a PF sequence then 1/f(−z) generates a PF sequence.
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