A Jump Inversion Theorem for the Degree Spectra
نویسنده
چکیده
In the present paper we continue the study of the properties of the spectra of structures as sets of degrees initiated in [11]. Here we consider the relationships between the spectra and the jump spectra. Our first result is that every jump spectrum is also a spectrum. The main result sounds like a Jump inversion theorem. Namely, we show that if a spectrum A is contained in the set of the jumps of the degrees in some spectrum B then there exists a spectrum C such that C ⊆ B and A is equal to the set of the jumps of the degrees in C.
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