Let P and Q be (partially) ordered sets with the same comparability graph. A bijection is constructed between the sets of linear extensions of P and Q such that the number of setups is preserved. This yields a common generaliTation of the comparability invariance of order dimension, setup number and
Linear extensions of random orders
โ Scribed by Graham Brightwell
- Publisher
- Elsevier Science
- Year
- 1994
- Tongue
- English
- Weight
- 621 KB
- Volume
- 125
- Category
- Article
- ISSN
- 0012-365X
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โฆ Synopsis
A popular model of random orders is obtained by taking two disjoint n-element antichains A, and Al, and putting in each relation in A, x A, with probability l/2, all the choices being made independently.
We estimate the number of linear extensions of such an ordered set, showing that this number is almost always very close to q(n!)', where q is a known constant.
We extend this result to produce estimates for the number of linear extensions of almost every n-element ordered set.
๐ SIMILAR VOLUMES
The central purpose of this paper is to prove the following theorem: let \((\Omega, \sigma\), \(u)\) be a complete probability space, \((B,\|\cdot\|)\) a normed linear space over the scalar field \(K, E: \Omega \rightarrow 2^{B}\) a separable random domain with linear subspace values, and \(f: \oper
We find asymptotic upper and lower bounds on the number of linear extensions of the containment ordering of subsets of a finite set. These agree in their most significant non-trivial terms. A related open question is described. L > 2"((n + 1)log 2 -4 log 2m -5 + o(1 ln)).