How to count trees?
Int. J. Mod. Phys. C16 (2005) 1527 We propose a new topological invariant of unlabeled trees of N nodes. The invariant is a set of Nx2 matrices of integers, with sum_j k^{d_{i,j}} and v_i as the matrix elements, where d_{i,j} are the elements of the distance matrix and v_i denotes i-th node's d...
Saved in:
Main Authors: | , , |
---|---|
Format: | Journal Article |
Language: | English |
Published: |
25-01-2005
|
Subjects: | |
Online Access: | Get full text |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Summary: | Int. J. Mod. Phys. C16 (2005) 1527 We propose a new topological invariant of unlabeled trees of N nodes. The
invariant is a set of Nx2 matrices of integers, with sum_j k^{d_{i,j}} and v_i
as the matrix elements, where d_{i,j} are the elements of the distance matrix
and v_i denotes i-th node's degree and k in N. To compare the invariant
calculated for possibly different graphs, the matrix rows are ordered with
respect to first column, and -- if necessary -- with respect to the second one.
We use the new invariant to evaluate from below the number of topologically
different unlabeled trees up to N=17. The results slightly exceed the
asymptotic evaluation of Otter. |
---|---|
DOI: | 10.48550/arxiv.cond-mat/0501594 |