4 papers
Ehrhart positivity for lattice path matroids
Luis Ferroni, Alejandro H. Morales, Greta Panova
We prove that all lattice path matroids are Ehrhart positive. This unifies and generalizes numerous results on the Ehrhart positivity of matroids developed over the last two decade…
Skew shapes, Ehrhart positivity and beyond
Luis Ferroni, Alejandro H. Morales, Greta Panova
A classical result by Kreweras (1965) allows one to compute the number of plane partitions of a given skew shape and bounded parts as certain determinants. We prove that these dete…
Grothendieck Shenanigans: Permutons from pipe dreams via integrable probability
Alejandro H. Morales, Greta Panova, Leonid Petrov +1
We study random permutations arising from reduced pipe dreams. Our main model is motivated by Grothendieck polynomials with parameter arising in K-theory of the flag variety.…
Minimal skew semistandard tableaux and the Hillman--Grassl correspondence
Alejandro H. Morales, Greta Panova, GaYee Park
Standard tableaux of skew shape are fundamental objects in enumerative and algebraic combinatorics and no product formula for the number is known. In 2014, Naruse gave a formula (N…