Abstract
Given an element x of a partial order P, a set S ⊂ P is said to be a cutset for x if S ∪ x meets every maximal chain of P and x is incomparable to every element of S. The cutset number of P is the minimum m such that every element of P has a cutset of size at most m. Let w(m, h) be the maximum width of a poset with height h and cutset number m. We determine the order of growth of w(m, h) for fixed m or fixed h: w(m, h)∈Θ(h ⌊m/2⌋) for fixed m and w(m, h)∈Θ(m h) for fixed h.
Similar content being viewed by others
References
M.Bell and J.Ginsburg (1984) Compact spaces and spaces of maximal complete subgraphs, Trans. Amer. Math. Soc. 283, 329–338.
M.El-Zahar and N.Sauer (1985) The length, the width, and the cutset-number of finite ordered sets, Order 2, 243–248.
M.El-Zahar and N.Zaguia (1985) Antichains and Cutsets, Combinatorics and Ordered Sets, Arcata, Calif., pp. 227–261, Contemporary Math 57, Amer. Math. Soc., Prov., RI 1986.
J.Ginsburg, I.Rival, and B.Sands (1986) Antichains and finite sets that meet all maximal chains, Cand. J. Math. 38(3), 619–632.
J.Ginsburg, B.Sands, and D.West (1989) A length-width inequality for partially ordered sets with two-element cutsets, J. Comb. Th. B 46, 232–239.
I.Rival and N.Zaguia (1985) Antichain cutsets, Order 1, 235–247.
N.Sauer and R. E.Woodrow (1984) Finite cutsets and finite antichains, Order 1, 35–46.
Author information
Authors and Affiliations
Additional information
Communicated by I. Rival
Research supported in part by ONR Grant N00014-85K0570 and by NSA/MSP Grant MDA904-90-H-4011.
Rights and permissions
About this article
Cite this article
Kézdy, A., Markert, M. & West, D.B. Wide posets with fixed height and cutset number. Order 7, 115–132 (1990). https://doi.org/10.1007/BF00383761
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00383761