4 papers
math.CO2026
Lower bounds on the -numbers of spheres without large missing faces
Isabella Novik, Hailun Zheng
We establish several new lower bounds on the -numbers of simplicial spheres without large missing faces. For this class of spheres, we derive bounds on the -numbers in terms…
math.CO2026
Simplicial spheres with
Isabella Novik, Hailun Zheng
For , Kalai (1987) characterized all simplicial -spheres with , and for and , Murai and Nevo (2013) characterized all simplicial -…
math.CO2025
Missing faces of neighborly and nearly neighborly polytopes and spheres
Isabella Novik, Hailun Zheng
For a -dimensional simplicial complex and , let be the number of -faces of and be the number of missing -faces of . In th…
math.CO2024
Transversal numbers of simplicial polytopes, spheres, and pure complexes
Isabella Novik, Hailun Zheng
We prove new upper and lower bounds on transversal numbers of several classes of simplicial complexes. Specifically, we establish an upper bound on the transversal numbers of pure…