Academic Staff and Fellows

Associate Professor Doctor of Sience
Department/Science  Graduate school/Science

Most discrete structures can be expressed in graph form. Graph theory represents a major research field of discrete mathematics. Here, research is conducted into extremal graph theory, which is the relationship between invariants and local substructures of the graph.

Heawood's counterexample to Kempe's "proof"

Research Area Graph Theory
Research Interests Degree conditions for the existence of cycles and trees with special property in graphs
Selected Publications (1) A note on two geometric paths with few crossings for points labeled by integers in the plane, A.Nakamoto, Y.Oda, M.Watanabe and T.Yamashita, Discrete Math.341 (2018) 1109--1113.

(2) On directed 2-factors in digraphs and 2-factors containing perfect matchings in bipartite graphs'',
S.Chiba and T.Yamashita, SIAM J.Discrete Math. 32
 (2018) 394--409.

(3) Degree Conditions for the Existence of Vertex-Disjoint Cycles and Paths: A Survey, S.Chiba and T.Yamashita, Graphs Combin.~34 (2018) 1--83.

(4) A note on degree sum conditions for 2-factors with a prescribed number of cycles in bipartite graphs, S.Chiba and T.Yamashita, Discrete Math.340  (2017), Pages 2871--2877.

(5) Degree sum conditions for vertex-disjoint cycles passing through specified vertices, S.Chiba and T.Yamashita, Discrete Math.340 (2017) 678--690.
Affiliated Academic Societies The Mathematical Society of Japan
(Undergraduate Course)
Kobe University
(Master's/Doctral Course)
Kobe University

Discrete Mathematics Laboratory

E-mail yamashita(at)
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Academic Staff and Fellows