3 citations · 5 across the 5 of their papers we have counts for
8 papers
Chromatic numbers for contact graphs of congruent cuboids
Søren Eilers, Rune Johansen, Rasmus Veber Rasmussen +1
We initiate the study of chromatic numbers for contact graphs of configurations of integer-sized cuboids in three dimensions, all of which are mutually congruent. Disallowing rotat…
The Polynomial Endomorphisms of Graph Algebras
Rune Johansen, Adam P. W. Sørensen, Wojciech Szymański
We investigate polynomial endomorphisms of graph -algebras and Leavitt path algebras. To this end, we define and analyze the coding graph corresponding to each such an endomor…
The Cuntz splice does not preserve -isomorphism of Leavitt path algebras over
Rune Johansen, Adam P. W. Sørensen
We show that the Leavitt path algebras and are not isomorphic as -algebras. There are two key ingredients in the proof. One is a partial a…
Flow equivalence of sofic beta-shifts
Rune Johansen
The Fischer, Krieger, and fiber product covers of sofic beta-shifts are constructed and used to show that every strictly sofic beta-shift is -sofic. Flow invariants based on the…
Visualizing automorphisms of graph algebras
James Emil Avery, Rune Johansen, Wojciech Szymanski
Graph C*-algebras have been celebrated as C*-algebras that can be seen, because many important properties may be determined by looking at the underlying graph. This paper introduce…
Is Every Irreducible Shift of Finite Type Flow Equivalent to a Renewal System?
Rune Johansen
Is every irreducible shift of finite type flow equivalent to a renewal system? For the first time, this variation of a classic problem formulated by Adler is investigated, and seve…
On Flow Equivalence of Sofic Shifts
Rune Johansen
The flow equivalence of sofic shifts is examined using results about the structure of the corresponding covers. A canonical cover generalising the left Fischer cover to arbitrary s…
On the Structure of Covers of Sofic Shifts
Rune Johansen
A canonical cover generalizing the left Fischer cover to arbitrary sofic shifts is introduced and used to prove that the left Krieger cover and the past set cover of a sofic shift…