Logic and Bounded-Width Rational Languages of Posets over Countable Scattered Linear Orderings
نویسنده
چکیده
In this paper we consider languages of labelled N -free posets over countable and scattered linear orderings. We prove that a language of such posets is series-rational if and only if it is recognizable by a finite depth-nilpotent algebra if and only if it is bounded-width and monadic second-order definable. This extends previous results on languages of labelled N -free finite and ω-posets and on languages of labelled countable and scattered linear orderings.
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