Abstract
A poset P = (X, ≺) is a unit OC interval order if there exists a representation that assigns an open or closed real interval I(x) of unit length to each x ∈ P so that x ≺ y in P precisely when each point of I (x) is less than each point in I (y). In this paper we give a forbidden poset characterization of the class of unit OC interval orders and an efficient algorithm for recognizing the class. The algorithm takes a poset P as input and either produces a representation or returns a forbidden poset induced in P.
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Shuchat, A., Shull, R. & Trenk, A.N. Unit Interval Orders of Open and Closed Intervals. Order 33, 85–99 (2016). https://doi.org/10.1007/s11083-015-9354-z
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DOI: https://doi.org/10.1007/s11083-015-9354-z