Erik Thörnblad

collaborators

2 papers

math.CO2018

Existence of symmetric maximal noncrossing collections of $k$ -element sets

Andrea Pasquali, Erik Thörnblad, Jakob Zimmermann

We investigate the existence of maximal collections of mutually noncrossing $k$ -element subsets of ${1, \dots, n}$ that are invariant under adding $k (mod n)$ to all…

math.CO2017

Counting Quasi-Idempotent Irreducible Integral Matrices

Erik Thörnblad, Jakob Zimmermann

Given any polynomial $p$ in $C [X]$ , we show that the set of irreducible matrices satisfying $p (A) = 0$ is finite. In the specific case $p (X) = X^{2} - n X$ , we count the number of irreducib…

Existence of symmetric maximal noncrossing collections of k-element sets

Counting Quasi-Idempotent Irreducible Integral Matrices

Existence of symmetric maximal noncrossing collections of $k$ -element sets