6 papers
Random GF(q)-representable matroids are not (b,c)-decomposable
Jorn van der Pol
We show that a random subset of the rank- projective geometry is, with high probability, not -decomposable: if is its colouring number, it does not…
Tuza's conjecture for binary geometries
Kazuhiro Nomoto, Jorn van der Pol
Tuza (A conjecture, in Proceedings of the Colloquia Mathematica Societatis Janos Bolyai, 1981) conjectured that for all graphs , where is the minimum siz…
Almost every matroid has an - or a -minor
Jorn van der Pol
We show that almost every matroid contains the rank-3 whirl or the complete-graphic matroid as a minor.
Enumeration of extensions of the cycle matroid of a complete graph
Peter Nelson, Shayla Redlin, Jorn van der Pol
We prove that the number of single element extensions of is . This is done using a characterization of extensions as "linear subclasses".
The number of partial Steiner systems and -partitions
Remco van der Hofstad, Rudi Pendavingh, Jorn van der Pol
We prove asymptotic upper bounds on the number of -partitions (paving matroids of fixed rank) and partial Steiner systems (sparse paving matroids of fixed rank), using a mixture…
Asymptotics of Symmetry in Matroids
Rudi Pendavingh, Jorn van der Pol
We prove that asymptotically almost all matroids have a trivial automorphism group, or an automorphism group generated by a single transposition. Additionally, we show that asympto…