226 reputation
15
bio website dcc.ufrj.br/~viniciussantos
location Brazil
age 28
visits member for 1 year
seen May 21 at 1:41
stats profile views 7

May
15
awarded  Caucus
May
11
answered tree that approximates the distances and total weight in graphs
May
4
awarded  Yearling
Apr
17
comment Eccentricity of vertices in a graph
Since k >= |V(G)|/2, if you take non-adjacent vertices u and v, you have |N(u)|+|N(v)|>= |V(G)|. Note that the total number of vertices is as big as the vertex set, hence, since they are not adjacent, there must be a repetition between the vertices of N(u) and N(v).
Apr
10
answered Eccentricity of vertices in a graph
Apr
9
comment Eccentricity of vertices in a graph
There are some trivial restrictions like the degree equals to |V(G)|-1 or |V(G)|-2. Is that the kind of restriction you are looking for?
Apr
5
revised Diameter of $k$-regular graph
Fixed a problem pointed by the author of the question.
Apr
5
comment Diameter of $k$-regular graph
Sure! Stupid me. I will fix it.
Apr
5
answered Diameter of $k$-regular graph
Apr
5
comment Diameter of $k$-regular graph
Is this true? Is it bounded by n/k or O(n/k)?
Oct
20
awarded  Teacher
Oct
15
answered Measure the connection between two nodes in a graph
Oct
15
awarded  Editor
Oct
15
revised Conditional merge of a sequence of DAGs / partial orders
Fixed a typo. "if" instead of "it".
Oct
15
comment Conditional merge of a sequence of DAGs / partial orders
As I said, I'm not sure the problem can be solved efficiently. It wouldn't surprise me if it's NP-hard.
Oct
15
answered Conditional merge of a sequence of DAGs / partial orders
Sep
15
awarded  Supporter
May
4
awarded  Autobiographer