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20152026
most citedIslands in minor-closed classes. I. Bounded treewidth and separators

20 citations · 85 across the 26 of their papers we have counts for

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Showing 2019Show all

7 papers · 1 filter

math.CO2019★ 8 cited

A new upper bound on the chromatic number of graphs with no odd minor

Sergey Norin, Zi-Xia Song

Gerards and Seymour conjectured that every graph with no odd minor is -colorable. This is a strengthening of the famous Hadwiger's Conjecture. Geelen et al. proved tha…

math.CO2019

Breaking the degeneracy barrier for coloring graphs with no minor

Sergey Norin, Luke Postle, Zi-Xia Song

In 1943, Hadwiger conjectured that every graph with no minor is -colorable for every . In the 1980s, Kostochka and Thomason independently proved that every gr…

math.CO2019

The smallest matroids with no large independent flat

Peter Nelson, Sergey Norin

We show that a simple rank- matroid with no -element independent flat has at least as many elements as the matroid defined as the direct sum of binary proje…

math.CO2019

Bounding the number of cycles in a graph in terms of its degree sequence

Zdeněk Dvořák, Natasha Morrison, Jonathan A. Noel +2

We give an upper bound on the number of cycles in a simple graph in terms of its degree sequence, and apply this bound to resolve several conjectures of Király and Arman and Tsatur…

math.CO2019

A lower bound on the average degree forcing a minor

Sergey Norin, Bruce Reed, Andrew Thomason +1

We show that for sufficiently large and for , there is a graph with average degree such that almost every graph with ver…

math.CO2019★ 2 cited

Asymptotic Density of Graphs Excluding Disconnected Minors

Rohan Kapadia, Sergey Norin, Yingjie Qian

For a graph , let where the maximum is taken over all graphs on vertices not containing as a minor. Thus…