365 search results - page 33 / 73 » On the combinatorics of Galois numbers |
COMBINATORICS
2007
14 years 11 months ago
2007
The distinguishing number ∆(X) of a graph X is the least positive integer n for which there exists a function f : V (X) → {0, 1, 2, · · · , n−1} such that no nonidentity ...
DAM
2007
14 years 11 months ago
2007
It is now well-documented that the structure of evolutionary relationships between a set of present-day species is not necessarily tree-like. The reason for this is that reticulat...
COMPGEOM
2004
ACM
15 years 5 months ago
2004
ACM
We prove that the lines tangent to four possibly intersecting convex polyhedra in 3 with n edges in total form Θ(n2 ) connected components in the worst case. In the generic ca...
COMBINATORICS
2006
14 years 12 months ago
2006
We give a parity reversing involution on noncrossing trees that leads to a combinatorial interpretation of a formula on noncrossing trees and symmetric ternary trees in answer to a...
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COMBINATORICS
2006
14 years 12 months ago
2006
A homomorphism from an oriented graph G to an oriented graph H is a mapping from the set of vertices of G to the set of vertices of H such that -----(u)(v) is an arc in H whenever...