Flows on flow-admissible signed graphs
WebHowever, such equivalence no longer holds for signed graphs. This motivates us to study how to convert modulo flows into integer-valued flows for signed graphs. In this paper, we generalize some early results by Xu and Zhang [ Discrete Math., 299 (2005), pp. 335--343], Schubert and Steffen [ European J. Combin., 48 (2015), pp. 34--47], and Zhu ... WebAug 29, 2024 · Many basic properties in Tutte's flow theory for unsigned graphs do not have their counterparts for signed graphs. However, signed graphs without long barbells in many ways behave like unsigned graphs from the point view of flows. In this paper, we study whether some basic properties in Tutte's flow theory remain valid for …
Flows on flow-admissible signed graphs
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WebAug 1, 2015 · Let t ≥ 1 be an integer and (G, σ) be a flow-admissible signed (2 t + 1)-regular graph. If G does not have a t-factor, then F c ((G, σ)) ≥ 2 + 2 2 t − 1. 5. r-minimal sets. This section studies the structural implications of the existence of a nowhere-zero (2 + 1 t)-flow on a signed (2 t + 1)-regular graph. Hence, it extends the first ... WebThe concept of integer flows on signed graphs naturally comes from the study of graphs embedded on nonorientable surfaces, where nowhere‐zero flow emerges as the dual notion to local tension. In 1983, Bouchet [2] proposed the following conjecture. Conjecture 1.2 (Bouchet [2]). Every flow‐admissible signed graph admits a nowhere‐zero 6‐flow.
WebSep 6, 2016 · A signed graph \((G, \sigma )\) is flow-admissible if there exists an orientation \(\tau \) and a positive integer k such that \((G, \sigma )\) admits a nowhere-zero k-flow.Bouchet (J Combin Theory Ser B 34:279–292, 1983) conjectured that every flow-admissible signed graph has a nowhere-zero 6-flow.In this paper, we show that each … WebAbstract. This paper is devoted to a detailed study of nowhere-zero flows on signed eulerian graphs. We generalise the well-known fact about the existence of nowhere-zero 2 2 2 2-flows in eulerian graphs by proving that every signed eulerian graph that admits an integer nowhere-zero flow has a nowhere-zero 4 4 4 4-flow.We also characterise …
WebApr 17, 2024 · Request PDF Six‐flows on almost balanced signed graphs In 1983, Bouchet conjectured that every flow‐admissible signed graph admits a nowhere‐zero 6‐flow. By Seymour's 6‐flow theorem ... WebMay 1, 2024 · Abstract. In 1983, Bouchet proposed a conjecture that every flow-admissible signed graph admits a nowhere-zero 6-flow. Bouchet himself proved that such signed …
WebApr 17, 2024 · Recently, Rollová et al proved that every flow-admissible signed cubic graph with two negative edges admits a nowhere-zero 7-flow, and admits a nowhere …
WebAn unsigned graph can also be considered as a signed graph with the all-positivesignature, i.e.E N(G,σ)=∅.Let(G,σ)beasignedgraph. ApathP inGiscalleda subdivided edge ofGifeveryinternalvertexofP isa2-vertex. Thesuppressed graph ofG,denoted by G, is the signed graph obtained from G by replacing each maximal subdivided edge P with a port hope contact usWebMar 15, 2024 · The flow number of a signed graph (G, Σ) is the smallest positive integer k such that (G, Σ) admits a nowhere-zero integer k-flow.In 1983, Bouchet (JCTB) conjectured that every flow-admissible signed graph has flow number at most 6. This conjecture remains open for general signed graphs even for signed planar graphs.A Halin graph … port hope council agendaWebApr 17, 2024 · Recently, Rollová et al proved that every flow-admissible signed cubic graph with two negative edges admits a nowhere-zero 7-flow, and admits a nowhere … irm chpg monacoWebSep 1, 2024 · Let (G, σ) be a 2-edge-connected flow-admissible signed graph. In this paper, we prove that (G, ... Bouchet A Nowhere-zero integral flows on a bidirected … port hope councillorsWebApr 16, 2024 · This motivates us to study how to convert modulo flows into integer-valued flows for signed graphs. In this paper, we generalize some early results by Xu and Zhang (Discrete Math. 299, 2005 ... irm chu bordeauxWebAuthors: DeVos, Matt; Li, Jiaao; Lu, You; Luo, Rong; Zhang, Cun-Quan; Zhang, Zhang Award ID(s): 1700218 Publication Date: 2024-05-01 NSF-PAR ID: 10212630 Journal … irm chris titusWebAug 28, 2024 · In 1983, Bouchet proposed a conjecture that every flow-admissible signed graph admits a nowhere-zero $6$-flow. Bouchet himself proved that such signed graphs admit nowhere-zero $216$-flows and ... port hope crash