Search Results
| Search type | Search syntax |
|---|---|
| Tags | [tag] |
| Exact | "words here" |
| Author |
user:1234 user:me (yours) |
| Score |
score:3 (3+) score:0 (none) |
| Answers |
answers:3 (3+) answers:0 (none) isaccepted:yes hasaccepted:no inquestion:1234 |
| Views | views:250 |
| Code | code:"if (foo != bar)" |
| Sections |
title:apples body:"apples oranges" |
| URL | url:"*.example.com" |
| Saves | in:saves |
| Status |
closed:yes duplicate:no migrated:no wiki:no |
| Types |
is:question is:answer |
| Exclude |
-[tag] -apples |
| For more details on advanced search visit our help page | |
Results tagged with graph-theory
Search options questions only
not deleted
user 31310
Questions about the branch of combinatorics called graph theory (not to be used for questions concerning the graph of a function). This tag can be further specialized via using it in combination with more specialized tags such as extremal-graph-theory, spectral-graph-theory, algebraic-graph-theory, topological-graph-theory, random-graphs, graph-colorings and several others.
0
votes
1
answer
159
views
Heuristics for lightweighted "cubic" spanning trees
I have the problem of calculating a good approximation of the minimimum-weight spanning tree with vertex-degrees in $\lbrace 1,3\rbrace$ of a complete symmetric graph, without parallel edges or self-l …
CommunityBot
- 1
1
vote
1
answer
79
views
Complexity of calculating the optimal amalgamation of an optimal cycle-cover
Let $G(V,E)$ be a complete symmetric graph with positive edge weights and let further $\mathcal{C}=\lbrace C_1,\,\cdots\,C_k\rbrace$ be the minimum-weight vertex-disjoint cycle cover.
The set $E$ of e …
CommunityBot
- 1
0
votes
1
answer
37
views
Cycle-Sculpturing with Minimal Vertex-Deletion
given a simple, finite and symmetric graph $G(V,E)$ with $n$ vertices and at least $n$ edges
Question:
how can the smallest set of vertices $W\subset V$ be calculated for which the graph induced by $ …
- 5,429
0
votes
1
answer
75
views
Dual equivalence of minimum feedback-vertex sets and cycle packing
it is known that the duals of feedback-set problems are set-packing problems; in the context of digraphs the feedback set are either a minimal set of vertices or edges that hit every oriented cycle; t …
CommunityBot
- 1
2
votes
1
answer
328
views
Worst case performance of heuristic for the non-Eulerian windy postman problem
The windy postman problem seeks the cheapest tour in a complete undirected graph, that traverses each edge at least once; the cost of traversing an edge is positive and may depend on the direction, in …
CommunityBot
- 1
1
vote
1
answer
93
views
Algorithmic complexity of calculating maximum weight $k$-regular subgraphs
Question:
what is known about the complexity of calculating the heaviest $k$-regular subgraph of a weighted symmetric graph if edge-weights can also be negative?
Please note that in contrast to $k$- …
CommunityBot
- 1
6
votes
1
answer
368
views
How does the complexity of calculating the Permanent imply the NP completeness of directed 3...
In their paper Two Approximation Algorithms for 3-Cycle Covers of Markus Bläser and Bodo Manthey it is stated that:
"...deciding whether an unweighted directed graph has a 3-cycle cover is already NP- …
- 13.2k
1
vote
1
answer
54
views
Complexity of maximum weight-sum matching for cycle graphs
I need to determine a matching with maximal weight-sum for a cycle graph with positive, negative and zero edge-weights.
Question:
What is the fastest way of calculating such a matching?
Because of t …
- 13.2k
0
votes
0
answers
23
views
Building hypercubes from the bottom up
let $H^k$ denote a $k$-dimensional hypercube in a complete symmetric graph $G(V,E)$ without self-loops and parallel edges; let $|V|=2^n$ be the number of vertices.
setting
$\mathbb{H}^0 := V$, i.e. th …
- 13.2k
2
votes
1
answer
224
views
Name for generalization of trees to digraphs
One definition of tree in graph theory could be as follows:
A tree is a(n undirected) graph for which there is a unique (undirected) path between any pair of vertices.
This suggest a possible defini …
- 24.2k
0
votes
0
answers
32
views
Enumeration of flat integral $K_4$
Question:
What is known about the enumeration of all $(a,b,c,d,e,f)\in\mathbb{N}^6_+: \\ \quad\operatorname{GCD}(a,b,c,d,e,f)=1\ \\ \land\ \exists \lbrace x_1,x_2,x_3,x_4\rbrace\subset\mathbb{E}^2:\ …
- 13.2k
2
votes
2
answers
202
views
Isometric embeddings of metric $K_{n+1}$ in $\mathbb{R}^n$
Question:
is it always possible to embed a complete, symmetric and metric graph $G$ with $n+1$ vertices isometrically in $\mathbb{R}^n$?
I'm convinced it must be true, but can't remember having seen …
- 13.2k
2
votes
1
answer
124
views
Constructing optimal Hamilton cycles from optimal Hamilton paths
Question:
can the shortest Hamilton cycle in a complete symmetric graph with weighted edges be constructed from the shortest Hamilton path in the same graph by connecting its ends and then exchanging …
- 4,219
1
vote
1
answer
501
views
Has this curious "duality" of weighted $K_4$ already been noticed?
A complete symmetric graph with $n=4$ vertices, i.e. a $K_4$ is the disjoint union of three perfect matchings $M_{\text{min}},M_{\text{mid}},M_{\text{max}}$ of which $M_{\text{min}}$ denotes the light …
CommunityBot
- 1
0
votes
0
answers
89
views
Relation of minimum spanning trees to the shortest Hamiltonian path problem
Spanning trees can be decomposed into a minimal set of maximal path graphs, whose vertices have degree two exactly if they also have degree two in the spanning tree; lets call these paths tree paths.
…
- 63.9k