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Tutte's 3-flow conjecture asserts that every $4$-edge-connected graph admits a nowhere-zero $3$-flow. We prove that this conjecture is true for every Cayley graph of valency at least four on any supersolvable group with a noncyclic Sylow…

Combinatorics · Mathematics 2022-03-08 Junyang Zhang , Sanming Zhou

Tutte's 3-flow conjecture asserts that every 4-edge-connected graph has a nowhere-zero 3-flow. In this note we prove that every regular graph of valency at least four admitting a solvable arc-transitive group of automorphisms admits a…

Combinatorics · Mathematics 2014-05-27 Xiangwen Li , Sanming Zhou

A function $f:N\rightarrow N$ is sublinear, if \[\lim_{x\rightarrow +\infty}\frac{f(x)}{x}=0.\] If $A$ is an Abelian group, $G$ is a graph and $\phi$ is an $A$-flow in $G$, then let $N(\phi)$ be the nullity of $\phi$, that is, the set of…

Discrete Mathematics · Computer Science 2020-10-08 Vahan Mkrtchyan

The Tutte polynomial of a graph G is a two-variable polynomial T(G;x,y) that encodes many interesting properties of the graph. We study the complexity of the following problem, for rationals x and y: take as input a graph G, and output a…

Computational Complexity · Computer Science 2008-07-20 Leslie Ann Goldberg , Mark Jerrum

In his article [J. Comb. Theory Ser. B 16 (1974), 168-174], Tutte called two graphs $T$-equivalent (i.e., codichromatic) if they have the same Tutte polynomial and showed that graphs $G$ and $G'$ are $T$-equivalent if $G'$ is obtained from…

Combinatorics · Mathematics 2025-01-22 Fengming Dong , Meiqiao Zhang

Tutte's $3$-flow conjecture states that every $4$-edge-connected graph admits a nowhere-zero $3$-flow. In this paper, we characterize all graphs with independence number at most $4$ that admit a nowhere-zero $3$-flow. The characterization…

Combinatorics · Mathematics 2017-07-24 Jiaao Li , Rong Luo , Yi Wang

In 1972 Tutte famously conjectured that every 4-edge-connected graph has a nowhere zero 3-flow; this is known to be equivalent to every 5-regular, 4-edge-connected graph having an edge orientation in which every in-degree is either 1 or 4.…

Combinatorics · Mathematics 2025-04-18 Michelle Delcourt , Reaz Huq , Pawel Pralat

Tutte initiated the study of nowhere-zero flows and proved the following fundamental theorem: For every graph $G$ there is a polynomial $f$ so that for every abelian group $\Gamma$ of order $n$, the number of nowhere-zero $\Gamma$-flows in…

Combinatorics · Mathematics 2017-01-26 Matt DeVos , Edita Rollová , Robert Šámal

In a recent paper, we studied the interaction between the automorphism group of a graph and its Tutte polynomial. More precisely, we proved that certain symmetries of graphs are clearly reflected by their Tutte polynomials. The purpose of…

Combinatorics · Mathematics 2018-02-26 Chbili Nafaa

Let $t_{i,j}$ be the coefficient of $x^iy^j$ in the Tutte polynomial $T(G;x,y)$ of a connected bridgeless and loopless graph $G$ with order $n$ and size $m$. It is trivial that $t_{0,m-n+1}=1$ and $t_{n-1,0}=1$. In this paper, we obtain…

Combinatorics · Mathematics 2017-05-30 Helin Gong , Mengchen Li , Xian'an Jin

We generalize Tutte's integer flows and the $d$-dimensional Euclidean flows of Mattiolo, Mazzuoccolo, Rajn\'{i}k, and Tabarelli to \emph{$d$-dimensional $p$-normed nowhere-zero flows} and define the corresponding flow index $\phi_{d,p}(G)$…

Combinatorics · Mathematics 2026-01-21 Chenxing Li , Jiaao Li , Rong Luo , Bo Su

Tutte conjectured in 1972 that every 4-edge connected graph has a nowhere-zero 3-flow. This has long been known to be equivalent to the conjecture that every 5-regular 4-edge-connected graph has an edge orientation in which every out-degree…

Combinatorics · Mathematics 2016-08-08 Pawel Pralat , Nick Wormald

Tutte's $3$-flow conjecture says that every $4$-edge-connected graph admits a nowhere-zero $3$-flow. Kochol (2001) showed that it is enough to prove this conjecture for $5$-edge-connected graphs. Former, Jaeger, Linial, Payan, and Tarsi…

Combinatorics · Mathematics 2022-05-16 Morteza Hasanvand

In this paper, we find recursive formulas for the Tutte polynomial of a family of small-world networks: Farey graphs, which are modular and have an exponential degree hierarchy. Then, making use of these formulas, we determine the number of…

Combinatorics · Mathematics 2015-06-17 Yunhua Liao , Yaoping Hou , Xiaoling Shen

The Tutte polynomial is a well-studied invariant of graphs and matroids. We first extend the Tutte polynomial from graphs to hypergraphs, and more generally from matroids to polymatroids, as a two-variable polynomial. Our definition is…

Combinatorics · Mathematics 2020-07-23 Olivier Bernardi , Tamas Kalman , Alex Postnikov

The Tutte polynomial of a graph G is a two-variable polynomial T(G;x,y) that encodes many interesting properties of the graph. We study the complexity of the following problem, for rationals x and y: given as input a planar graph G,…

Computational Complexity · Computer Science 2012-10-03 Leslie Ann Goldberg , Mark Jerrum

We introduce the ``trivariate Tutte polynomial" of a signed graph as an invariant of signed graphs up to vertex switching that contains among its evaluations the number of proper colorings and the number of nowhere-zero flows. In this, it…

Combinatorics · Mathematics 2022-03-01 Andrew Goodall , Bart Litjens , Guus Regts , Lluis Vena

The Tutte polynomial of a graph or a matroid, named after W. T. Tutte, has the important universal property that essentially any multiplicative graph or network invariant with a deletion and contraction reduction must be an evaluation of…

Combinatorics · Mathematics 2012-03-02 Criel Merino , Marcelino Ramírez-Ibáñez , Guadalupe Rodríguez Sanchez

It has been known since the work of Tutte that the value of the chromatic polynomial of planar triangulations at $(3+\sqrt{5})/2$ has a number of remarkable properties. We investigate to what extent Tutte's relations characterize planar…

Combinatorics · Mathematics 2015-12-24 Ian Agol , Vyacheslav Krushkal

Let $S,T$ be two distinct finite Abelian groups with $|S|=|T|$. A fundamental theorem of Tutte shows that a graph admits a nowhere-zero $S$-flow if and only if it admits a nowhere-zero $T$-flow. Jaeger, Linial, Payan and Tarsi in 1992…

Combinatorics · Mathematics 2020-09-16 Miaomiao Han , Jiaao Li , Xueliang Li , Meiling Wang
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