University of Haifa

output

19922026

most citedThe new world atlas of artificial night sky brightness

1.7k citations

Showing 2018 · math.COShow all

7 papers · 2 filters

math.CO2018★ 3 cited

Acyclic subgraphs with high chromatic number

Safwat Nassar, Raphael Yuster

For an oriented graph $G$ , let $f (G)$ denote the maximum chromatic number of an acyclic subgraph of $G$ . Let $f (n)$ be the smallest integer such that every oriented graph $G$ with…

math.CO2018

Passing through a stack $k$ times with reversals

Toufik Mansour, Howard Skogman, Rebecca Smith

We consider a stack sorting algorithm where only the appropriate output values are popped from the stack and then any remaining entries in the stack are run through the stack in re…

math.CO2018★ 7 cited

Permutations avoiding 312 and another pattern, Chebyshev polynomials and longest increasing subsequences

Toufik Mansour, Gökhan Yıldırım

We study the longest increasing subsequence problem for random permutations avoiding the pattern $312$ and another pattern $τ$ under the uniform probability distribution. We determ…

math.CO2018★ 1 cited

Enumerations of bargraphs with respect to corner statistics

Toufik Mansour, Gökhan Yıldırım

We study the enumeration of bargraphs with respect to some corner statistics. We find generating functions for the number of bargraphs that tracks the corner statistics of interest…

math.CO2018

The components of the singular locus of a component of a Springer fiber over x^2 = 0

Ronit Mansour, Anna Melnikov

For $x \in E n d (K^{n})$ satisfying $x^{2} = 0$ let $F_{x}$ be the variety of full flags stable under the action of $x$ (Springer fiber over $x$ ). The full classification of the components…

math.CO2018★ 4 cited

Cooperative colorings of trees and of bipartite graphs

Ron Aharoni, Eli Berger, Maria Chudnovsky +2

Given a system $(G_{1}, \dots, G_{m})$ of graphs on the same vertex set $V$ , a cooperative coloring is a choice of vertex sets $I_{1}, \dots, I_{m}$ , such that $I_{j}$ is independent in $G…