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Leen Droogendijk
  • Member for 8 years, 9 months
  • Last seen more than a week ago
  • Vianen, the Netherlands
16 votes
Accepted

Every simple planar graph with $\delta\geq 3$ has an adjacent pair with $deg(u)+deg(v)\leq 13$

10 votes
Accepted

Special subdivision of numbers from 1 to 99

9 votes
Accepted

Graph partition that span a third of edges

8 votes
Accepted

Does every "balloon" (dragon, tadpole, canoe paddle) admit a graceful labeling?

8 votes
Accepted

Degree sequence on graphs

7 votes
Accepted

$\chi(G)+\chi(G')\leq n+1$

6 votes
Accepted

Chromatic Contradiction Proof

6 votes
Accepted

Any bipartite graph has a matching that covers each vertex of maximum degree

5 votes
Accepted

Counting "double bonds" in graphs

5 votes
Accepted

How to prove that there is a monotone path in a graph with a length of greater or equal to average degree?

5 votes
Accepted

Does 3-partite graph with at least n+1 edges per vertex have a triangle?

5 votes
Accepted

Symmetric difference of cycles

5 votes
Accepted

Example of Exponential Graph

5 votes

Combinatorics: Binary Strings

5 votes

Chromatic index of a complete graph

5 votes
Accepted

Tripartite n+1-regular graph containing a triangle

5 votes
Accepted

Self complementary graph with a pendant vertex

5 votes
Accepted

Partition graph into disjoint beams

4 votes

Domino Trains Questions

4 votes
Accepted

Graph with cycles of every length

4 votes
Accepted

Chromatic number and vertex covering number

4 votes

Perfect matching in k-cubes

4 votes

Prove that a local-minimum spanning tree is also a minimum spanning tree.

4 votes
Accepted

Perfect Coverings

4 votes

Advanced Counting Puzzle

4 votes
Accepted

Prove that if $deg (v) > \frac{k}{2}$ for every $v \in V(G)$ then $G$ is Hamitonian.

4 votes
Accepted

Black and white beads on a circle

4 votes
Accepted

Why can the complete graph $K_{16}$ be partitioned into three copies of the Clebsch graph?

4 votes

How to prove a graph asymmetric?

4 votes
Accepted

Prove that the Möbius ladder and the toroidal ladder are non-isomorphic graphs.

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