14 citations · 78 across the 33 of their papers we have counts for
4 papers · 1 filter
A structural characterisation of Av(1324) and new bounds on its growth rate
David Bevan, Robert Brignall, Andrew Elvey Price +1
We establish an improved lower bound of 10.271 for the exponential growth rate of the class of permutations avoiding the pattern 1324, and an improved upper bound of 13.5. These re…
The Möbius function of permutations with an indecomposable lower bound
Robert Brignall, David Marchant
We show that the Möbius function of an interval in a permutation poset where the lower bound is sum (resp. skew) indecomposable depends solely on the sum (resp. skew) indecomposabl…
A counterexample regarding labelled well-quasi-ordering
Robert Brignall, Michael Engen, Vincent Vatter
Korpelainen, Lozin, and Razgon conjectured that a hereditary property of graphs which is well-quasi-ordered by the induced subgraph order and defined by only finitely many minimal…
Characterising inflations of monotone grid classes of permutations
Michael Albert, Aistis Atminas, Robert Brignall
We characterise those permutation classes whose simple permutations are monotone griddable. This characterisation is obtained by identifying a set of nine substructures, at least o…