Steven Noble

Counting delta-matroids

Delta-matroids were introduced by Bouchet in the late 1980s but, until recently, have not been studied a great deal since. Examples of them arise from ribbon graphs and matrices, in much the same way as matroids arise from graphs and matrices. Following Iain Moffatt’s talk in the autumn, we give a gentle introduction / reminder of delta-matroids and then describe joint work with Daryl Funk and Dillon Mayhew giving bounds on the number of labelled delta-matroids, including results almost analogous to those for matroids. (There will not be too much matroid theory!)