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The element splitting operation on a graphic matroid, in general may not yield a cographic matroid. In this paper, we give a necessary and sufficient condition for the graphic matroid to yield cographic matroid under the element splitting…

Combinatorics · Mathematics 2018-10-09 S. B. Dhotre , P. P. Malavadkar

Splitting operation in Matroid Theory does not preserve graphicness, connectedness, cographicness, etc. Also, the splitting of binary gammoid does not necessarily be binary gammoid after splitting. We have characterized a class of graphic…

Combinatorics · Mathematics 2023-10-06 S. D. Solanki , S. B. Dhotre

Raghunathan at al. [9] introduced splitting operation with respect to a pair of element for binary matroid and characterized Eulerian binary matroids using it. In general, the splitting operation does not preserve the graphicness property…

Combinatorics · Mathematics 2020-02-13 Ganesh Mundhe , K. V. Dalvi

A matroid $N$ is a lift of a binary matroid $M$, if $N=Q\backslash X$ when $Q/X=M$ for some binary matroid $Q$ and $X \subseteq E(Q)$ and is called an elementary lift of $M$, if $|X|=1$. A splitting operation on a binary matroid can result…

Combinatorics · Mathematics 2023-01-06 Shital D. Solanki , Ganesh Mundhe , S. B. Dhotre

An excluded minor characterization for the class of binary signed-graphic matroids with graphic cocircuits is provided. In this report we present the necessary computations for the case analysis in the proof.

Combinatorics · Mathematics 2012-05-07 Konstantinos Papalamprou , Leonidas Pitsoulis

In this paper we employ Tutte's theory of bridges to derive a decomposition theorem for binary matroids arising from signed graphs. The proposed decomposition differs from previous decomposition results on matroids that have appeared in the…

Combinatorics · Mathematics 2015-03-17 Konstantinos Papalamprou , Leonidas Pitsoulis

We introduce the notion of graphic cocircuits and show that a large class of regular matroids with graphic cocircuits belongs to the class of signed-graphic matroids. Moreover, we provide an algorithm which determines whether a cographic…

Discrete Mathematics · Computer Science 2009-09-29 Konstantinos Papalamprou , Leonidas Pitsoulis

We introduce delta-graphic matroids, which are matroids whose bases form graphic delta-matroids. The class of delta-graphic matroids contains graphic matroids as well as cographic matroids and is a proper subclass of the class of regular…

Combinatorics · Mathematics 2022-10-05 Duksang Lee , Sang-il Oum

Zaslavsky introduced the concept of lifted-graphic matroid. For binary matroids, a binary elementary lift can be defined in terms of the splitting operation. In this paper, we give a method to get a forbidden-minor characterization for the…

Combinatorics · Mathematics 2019-10-15 Ganesh Mundhe , Y. M. Borse , K. V. Dalvi

Let $M$ be a 3-connected binary matroid and let $Y(M)$ be the set of elements of $M$ avoiding at least $r(M)+1$ non-separating cocircuits of $M$. Lemos proved that $M$ is non-graphic if and only if $Y(M)\neq\emp$. We generalize this result…

Combinatorics · Mathematics 2012-11-27 João Paulo Costalonga

In this work we provide a decomposition theorem for the class of quaternary and non-binary signed-graphic matroids. This generalizes previous results for binary signed-graphic matroids and graphic matroids, and it provides the theoretical…

Combinatorics · Mathematics 2015-10-26 Leonidas Pitsoulis , Eleni-Maria Vretta

We provide a combinatorial study of split matroids, a class that was motivated by the study of matroid polytopes from a tropical geometry point of view. A nice feature of split matroids is that they generalize paving matroids, while being…

Combinatorics · Mathematics 2022-02-10 Kristóf Bérczi , Tamás Király , Tamás Schwarcz , Yutaro Yamaguchi , Yu Yokoi

Fleischner introduced the idea of splitting a vertex of degree at least three in a connected graph and used the operation to characterize Eulerian graphs. Raghunathan et. al. extended the splitting operation from graphs to binary matroids.…

Combinatorics · Mathematics 2018-09-28 S. B. Dhotre , P. P. Malavadkar

A matroid M is unbreakable if it is connected and M/F is connected for every flat F of M . Oxley and Pfeil characterized the unbreakable graphic matroids, and Fife, Mayhew, Oxley, and Semple characterized the graphs underlying 3-connected…

Combinatorics · Mathematics 2026-05-14 Sayantani Bhattacharya , John David Clifton , Zach Walsh

Given a matroid together with a coloring of its ground set, a subset of its elements is called rainbow colored if no two of its elements have the same color. We show that if a binary matroid of rank $r$ is colored with exactly $r$ colors,…

Combinatorics · Mathematics 2021-09-02 Kristóf Bérczi , Tamás Schwarcz

Frame matroids and lifted-graphic matroids are two interesting generalizations of graphic matroids. Here we introduce a new generalization, {\em quasi-graphic matroids}, that unifies these two existing classes. Unlike frame matroids and…

Combinatorics · Mathematics 2017-04-25 Jim Geelen , Bert Gerards , Geoff Whittle

Zaslavsky (1991) introduced a graphical structure called a biased graph and used it to characterize all single-element coextensions and elementary lifts of graphic matroids. We introduce a new, dual graphical structure that we call a…

Combinatorics · Mathematics 2024-02-01 Daniel Slilaty , Thomas Zaslavsky

We give polynomial-time randomized algorithms for computing the girth and the cogirth of binary matroids that are low-rank perturbations of graphic matroids.

Combinatorics · Mathematics 2015-10-15 Jim Geelen , Rohan Kapadia

Let $M$ be a $3$-connected matroid. A pair $\{e,f\}$ in $M$ is detachable if $M \backslash e \backslash f$ or $M / e / f$ is $3$-connected. Williams (2015) proved that if $M$ has at least 13 elements, then at least one of the following…

Combinatorics · Mathematics 2025-09-15 Nick Brettell , Charles Semple , Gerry Toft

Seymour's Decomposition Theorem for regular matroids states that any matroid representable over both GF(2) and GF(3) can be obtained from matroids that are graphic, cographic, or isomorphic to R10 by 1-, 2-, and 3-sums. It is hoped that…

Combinatorics · Mathematics 2015-03-13 Dillon Mayhew , Geoff Whittle , Stefan H. M. van Zwam
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