Zobrazeno 1 - 10
of 14
pro vyhledávání: '"Kazuhide Hirohata"'
Publikováno v:
Graphs and Combinatorics. 36:1927-1945
In this paper, we consider a general degree sum condition sufficient to imply the existence of $k$ vertex-disjoint chorded cycles in a graph $G$. Let $\sigma_t(G)$ be the minimum degree sum of $t$ independent vertices of $G$. We prove that if $G$ is
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::4f568c517bb6a72f738014399415af5b
https://doi.org/10.1007/s00373-020-02227-z
https://doi.org/10.1007/s00373-020-02227-z
Publikováno v:
Graphs and Combinatorics. 34:1691-1711
A graph G of order $$n\ge 3$$ is pancyclic if G contains a cycle of each possible length from 3 to n, and vertex pancyclic (edge pancyclic) if every vertex (edge) is contained on a cycle of each possible length from 3 to n. A chord of a cycle is an e
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::cff728558a13ad7b22ff83a9da2e4162
https://doi.org/10.1007/s00373-018-1960-2
https://doi.org/10.1007/s00373-018-1960-2
Publikováno v:
Discrete Mathematics. 341:203-212
This paper considers a degree sum condition sufficient to imply the existence of k vertex-disjoint cycles in a graph G . For an integer t ≥ 1 , let σ t ( G ) be the smallest sum of degrees of t independent vertices of G . We prove that if G has or
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::d42b72a8824ef7d4c6fa2912aaf6e197
https://doi.org/10.1016/j.disc.2017.08.030
https://doi.org/10.1016/j.disc.2017.08.030
Publikováno v:
Graphs and Combinatorics. 32:2295-2313
A chord is an edge between two vertices of a cycle that is not an edge on the cycle. If a cycle has at least one chord, then the cycle is called a chorded cycle, and if a cycle has at least two chords, then the cycle is called a doubly chorded cycle.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::544f3d5b25854cda0ab1073a8fa16d99
https://doi.org/10.1007/s00373-016-1729-4
https://doi.org/10.1007/s00373-016-1729-4
Publikováno v:
Discrete Mathematics. 338:2051-2071
In a graph G , we say a cycle C : v 1 , v 2 , ? , v k , v 1 is chorded if its vertices induce an additional edge (chord) which is not an edge of the cycle. The cycle C is doubly chorded if there are at least two such chords. In this paper we show a s
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::ae08d7b839e529864b9ccd51faa6fa9e
https://doi.org/10.1016/j.disc.2015.05.010
https://doi.org/10.1016/j.disc.2015.05.010
Publikováno v:
SIAM Journal on Discrete Mathematics. 29:1030-1041
Bollobas and Thomason showed that a multigraph of order $n$ and size at least $n+c\,(c\ge 1)$ contains a cycle of length at most $2(\lfloor n/c\rfloor+1)\lfloor \log_2 2c\rfloor$. We show in this paper that a multigraph (with no loop) of order $n$ an
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::12afaf2a061ba718588fdef2ea28949d
https://doi.org/10.1137/130929837
https://doi.org/10.1137/130929837
Publikováno v:
Journal of Combinatorics. 4:105-122
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::86a86d5ed37ab709e3c4fc79bcb64b25
https://doi.org/10.4310/joc.2013.v4.n1.a6
https://doi.org/10.4310/joc.2013.v4.n1.a6
Autor:
Kazuhide Hirohata
Publikováno v:
Discrete Mathematics. 250(1-3):109-123
An independent set S of a graph G is said to be essential if S has a pair of vertices that are distance two apart in G. For S ⊆ V(G) with S ≠ φ, let Δ(S) = max{dG(x)|x ∈ S}. We prove the following theorem. Let k ≥ 2 and let G be a k-connect
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::4e7bc7d48d78ba6c56914e4d466c3a92
Publikováno v:
Journal of Graph Theory. 39:265-282
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::dc5d4a2440d79455c0476383d7ef33dc
https://doi.org/10.1002/jgt.10028
https://doi.org/10.1002/jgt.10028
Autor:
Kazuhide Hirohata
Publikováno v:
Graphs and Combinatorics. 16:269-273
Let G be a 2-connected graph with maximum degree Δ (G)≥d, and let x and y be distinct vertices of G. Let W be a subset of V(G)−{x, y} with cardinality at most d−1. Suppose that max{dG(u), dG(v)}≥d for every pair of vertices u and v in V(G)
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::dea6147edae575400c46e7040b406ecd
https://doi.org/10.1007/pl00007222
https://doi.org/10.1007/pl00007222