Skip to main content

All Questions

3 votes
1 answer
34 views

Is There any Untraceable Generalized Petersen Graph?

The Petersen graph is one of the example of graph which is not Hamiltonian. Can we find an example among the generalized Petersen graph which doesn't have Hamiltonian path (untraceable)?
user966's user avatar
  • 1,949
1 vote
1 answer
36 views

What kind of graph is this? Hamiltonian by association?

Here is an example of a connected cycle using the edges: $ABC-BCD-BCE-CDE-BDE-ABE-ACE-ADE-ACD$ Here $ABC$ shares $BC$ with $BCD$, $BCD$ shares $BC$ with $BCE$, ... , $ACD$ shares $AC$ with $ABC$. ...
Baklava Gain's user avatar
0 votes
1 answer
774 views

Graph problem about roads built between towns [closed]

There are 10 cities in a country. The Government starts to build direct roads between the cities, but with random access, it can build direct road between two cities even if there is already another ...
Pol's user avatar
  • 21
2 votes
1 answer
573 views

Prove Herschel graph is nonhamiltonian

Let us denote by $c(G)$ the number of components of graph $G$. Theory: For a hamiltonain graph we have $c(G-S)\leq|S|$ for any set $S$ of vertices of $G$. How can I show that Herschel graph is ...
Fatemeh Davoudi's user avatar
0 votes
2 answers
264 views

Degree sequence in a maximal planar graph

Two isomorphic 9 vertex graphs Given the ordered degree sequence of a hamiltonian circuit in a maximal planar graph. Can we have different maximal planar graphs with the same ordered degree sequence? ...
PatL's user avatar
  • 13
1 vote
1 answer
224 views

Ultra-Hamiltonian cycle

Ultra-Hamiltonian cycling is defined to be a closed walk that visits every vertex exactly once, except for at most one vertex that visits more than once. Question:- Prove that it is NP-hard to ...
Nitin Kumar Chauhan's user avatar
1 vote
0 answers
58 views

Is there any new developments on the Barnette's conjecture?

When I searching for interesting math problems. I find there is a graph theory conjecture called the Barnette's conjecture. The statement is: Is every bipartite simple polyhedron Hamiltonian? A early ...
Zizheng Yang's user avatar
5 votes
1 answer
808 views

Definition of a separating triangle in planar graph

In Bill Tutte's famous book Graph Theory as I Have Known It he discusses Hassler Whitney's theorem on Hamiltonian cycles in planar graphs, summarising it thus: Any strict triangulation in which there ...
HughHughTeotl's user avatar
7 votes
1 answer
2k views

How does Grinberg's theorem work?

Grinberg's theorem is a condition used to prove the existence of an Hamilton cycle on a planar graph. It is formulated in this way: Let $G$ be a finite planar graph with a Hamiltonian cycle $C$, ...
icebit's user avatar
  • 173
9 votes
1 answer
2k views

All 4-connected planar graphs are Hamiltonian-connected

I started reading Thomassen's paper A Theorem on Paths in Planar Graphs, where he proves one of Plummer's conjectures: Every $4$-connected planar graph is Hamiltonian-connected. Context. Recall that ...
Prism's user avatar
  • 11.3k
1 vote
1 answer
523 views

Is there a non-planar, non-hamiltonian and eulerian graph?

I'm trying to find a graph that is non-planar, non-hamiltonian and eulerian but I can't find anyone. Is this possible? Thanks
emee's user avatar
  • 29
3 votes
1 answer
1k views

3-connected planar bipartite graph without a Hamiltonian path

I'm stuck with exercise 18.1.5 of Bondy & Murty's Graph Theory book which asks for an example of a 3-connected planar bipartite graph on fourteen vertices that is not traceable (that is, which has ...
user594756's user avatar
0 votes
0 answers
39 views

Are there any software or libraries(in some language) which draws all the planar graphs given the number of vertices?

I am working on interrelationships between planar and Hamiltonian graphs and for the purpose I need planar graphs for inspection. Since their number grows asymptotically, I cannot approach it manually....
NotNotLogic's user avatar
3 votes
1 answer
570 views

Edge-disjoint Hamiltonian cycles in a planar graph.

Is it possible to have a planar graph with two edge-disjoint Hamiltonian cycles?
prajwal's user avatar
  • 65
1 vote
2 answers
150 views

Number of Hamiltonian Cycles in planar chordal graph

I have a given planar chordal graph $G$. Due to the construction of $G$ I know that there exists at least one Hamiltonian cycle in $G$. My question is: How many Hamiltonian cycles are in $G$? (an ...
gue's user avatar
  • 328

15 30 50 per page