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20182026
most citedDuality theorems for stars and combs I: Arbitrary stars and combs

12 citations · 34 across the 21 of their papers we have counts for

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Showing 2020 · math.COShow all

11 papers · 2 filters

math.CO2020

Edge-connectivity and tree-structure in finite and infinite graphs

Christian Elbracht, Jan Kurkofka, Maximilian Teegen

We show that every graph admits a canonical tree-like decomposition into its -edge-connected pieces for all simultaneously.

math.CO2020

Halin's end degree conjecture

Stefan Geschke, Jan Kurkofka, Ruben Melcher +1

An end of a graph is an equivalence class of rays, where two rays are equivalent if there are infinitely many vertex-disjoint paths between them in . The degree of an end is…

math.CO2020

The Farey graph is uniquely determined by its connectivity

Jan Kurkofka

We show that, up to minor-equivalence, the Farey graph is the unique minor-minimal graph that is infinitely edge-connected but such that every two vertices can be finitely separate…

math.CO2020

End-faithful spanning trees in graphs without normal spanning trees

Carl Bürger, Jan Kurkofka

Schmidt characterised the class of rayless graphs by an ordinal rank function, which makes it possible to prove statements about rayless graphs by transfinite induction. Halin aske…

math.CO2020★ 2 cited

Every infinitely edge-connected graph contains the Farey graph or as a minor

Jan Kurkofka

We show that every infinitely edge-connected graph contains the Farey graph or as a minor. These two graphs are unique with this property up to minor-equival…

math.CO2020★ 12 cited

Duality theorems for stars and combs I: Arbitrary stars and combs

Carl Bürger, Jan Kurkofka

Extending the well-known star-comb lemma for infinite graphs, we characterise the graphs that do not contain an infinite comb or an infinite star, respectively, attached to a given…

math.CO2020

Duality theorems for stars and combs II: Dominating stars and dominated combs

Carl Bürger, Jan Kurkofka

In a series of four papers we determine structures whose existence is dual, in the sense of complementary, to the existence of stars or combs. Here, in the second paper of the seri…

math.CO2020

Duality theorems for stars and combs III: Undominated combs

Carl Bürger, Jan Kurkofka

In a series of four papers we determine structures whose existence is dual, in the sense of complementary, to the existence of stars or combs. Here, in the third paper of the serie…

math.CO2020

Duality theorems for stars and combs IV: Undominating stars

Carl Bürger, Jan Kurkofka

In a series of four papers we determine structures whose existence is dual, in the sense of complementary, to the existence of stars or combs. In the first paper of our series we d…

math.CO2020★ 1 cited

A tree-of-tangles theorem for infinite tangles

Ann-Kathrin Elm, Jan Kurkofka

Carmesin has extended Robertson and Seymour's tree-of-tangles theorem to the infinite tangles of locally finite infinite graphs. We extend it further to the infinite tangles of all…

math.CO2020★ 10 cited

Approximating infinite graphs by normal trees

Jan Kurkofka, Ruben Melcher, Max Pitz

We show that every connected graph can be approximated by a normal tree, up to some arbitrarily small error phrased in terms of neighbourhoods around its ends. The existence of suc…