On Nowhere Zero 4-Flows in Regular Matroids
نویسندگان
چکیده
Walton and Welsh proved that if a co-loopless regular matroid M does not have minor in {M(K(3,3)),M∗(K5)}, then admits nowhere zero 4-flow. Lai, Li Poon {M(K5),M∗(K5)}, We prove {M((P10)¯3 ),M∗(K5)}, 4-flow where (P10)¯3 is the graph obtained from Petersen P10by contracting 3 edges of perfect matching. As both M(K3,3) M(K5) are contractions M((P10)¯3), our result extends results Poon.
منابع مشابه
Nowhere zero 4-flow in regular matroids
Jensen and Toft [10] conjectured that every 2-edge-connected graph without a K5minor has a nowhere zero 4-flow. Walton and Welsh [24] proved that if a coloopless regular matroid M does not have a minor in {M(K3,3),M(K5)}, then M admits a nowhere zero 4-flow. In this note, we prove that if a coloopless regular matroid M does not have a minor in {M(K5),M(K5)}, then M admits a nowhere zero 4-flow....
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ژورنال
عنوان ژورنال: Theory and applications of graphs
سال: 2023
ISSN: ['2470-9859']
DOI: https://doi.org/10.20429/tag.2023.100201