JCT
2008
13 years 11 months ago
2008
A 4-graph is odd if its vertex set can be partitioned into two sets so that every edge intersects both parts in an odd number of points. Let b(n) = max n 3 + (n - ) 3 = 1 2 + o...
EJC
2006
13 years 11 months ago
2006
The problem of counting plane trees with n edges and an even or an odd number of leaves has been recently studied by Eu, Liu and Yeh, in connection with an identity on coloring ne...
GD
2007
Springer
14 years 5 months ago
2007
Springer
The odd crossing number of G is the smallest number of pairs of edges that cross an odd number of times in any drawing of G. We show that there always is a drawing realizing the o...