Results 11 to 20 of about 413 (64)
Decomposing tournaments into paths
Abstract We consider a generalisation of Kelly's conjecture which is due to Alspach, Mason, and Pullman from 1976. Kelly's conjecture states that every regular tournament has an edge decomposition into Hamilton cycles, and this was proved by Kühn and Osthus for large tournaments. The conjecture of Alspach, Mason, and Pullman asks for the minimum number
Allan Lo +3 more
wiley +1 more source
Dissecting a square into congruent polygons [PDF]
We study the dissection of a square into congruent convex polygons. Yuan \emph{et al.} [Dissecting the square into five congruent parts, Discrete Math. \textbf{339} (2016) 288-298] asked whether, if the number of tiles is a prime number $\geq 3$, it is ...
Hui Rao, Lei Ren, Yang Wang
doaj +1 more source
Loose Hamiltonian cycles forced by large $(k-2)$-degree - sharp version [PDF]
We prove for all $k\geq 4$ and $1\leq ...
Bastos, Josefran de Oliveira +4 more
core +3 more sources
Hamiltonian paths on Platonic graphs
We develop a combinatorial method to show that the dodecahedron graph has, up to rotation and reflection, a unique Hamiltonian cycle. Platonic graphs with this property are called topologically uniquely Hamiltonian. The same method is used to demonstrate topologically distinct Hamiltonian cycles on the icosahedron graph and to show that a regular graph
Brian Hopkins
wiley +1 more source
Old and new generalizations of line graphs
Line graphs have been studied for over seventy years. In 1932, H. Whitney showed that for connected graphs, edge‐isomorphism implies isomorphism except for K3 and K1,3. The line graph transformation is one of the most widely studied of all graph transformations.
Jay Bagga
wiley +1 more source
Longest cycles in certain bipartite graphs
Let G be a connected bipartite graph with bipartition (X, Y) such that |X| ≥ |Y|(≥2), n = |X| and m = |Y|. Suppose, for all vertices x ∈ X and y ∈ Y, dist(x, y) = 3 implies d(x) + d(y) ≥ n + 1. Then G contains a cycle of length 2m. In particular, if m = n, then G is hamiltomian.
Pak-Ken Wong
wiley +1 more source
Hamiltonicities of Double Domination Critical and Stable Claw-Free Graphs
A graph G with the double domination number γ×2(G) = k is said to be k- γ×2-critical if γ×2 (G + uv) < k for any uv ∉ E(G). On the other hand, a graph G with γ×2 (G) = k is said to be k-γ×2+$k - \gamma _{ \times 2}^ + $-stable if γ×2 (G + uv) = k for any
Kaemawichanurat Pawaton
doaj +1 more source
Uniquely hamiltonian graphs for many sets of degrees [PDF]
We give constructive proofs for the existence of uniquely hamiltonian graphs for various sets of degrees. We give constructions for all sets with minimum 2 (a trivial case added for completeness), all sets with minimum 3 that contain an even number (for ...
Gunnar Brinkmann, Matthias De Pauw
doaj +1 more source
Lower Bound on the Number of Hamiltonian Cycles of Generalized Petersen Graphs
In this paper, we investigate the number of Hamiltonian cycles of a generalized Petersen graph P (N, k) and prove that Ψ(P(N,3))⩾N⋅αN,\Psi ( {P ( {N,3} )} ) \ge N \cdot {\alpha _N}, where Ψ(P(N, 3)) is the number of Hamiltonian cycles of P(N, 3) and αN ...
Lu Weihua, Yang Chao, Ren Han
doaj +1 more source
Hamiltonian‐connected graphs and their strong closures
Let G be a simple graph of order at least three. We show that G is Hamiltonian‐connected if and only if its strong closure is Hamiltonian‐connected. We also give an efficient algorithm to compute the strong closure of G.
Pak-Ken Wong
wiley +1 more source

