English

An Approximate Version of the Strong Nine Dragon Tree Conjecture

Combinatorics 2020-07-15 v3

Abstract

The Strong Nine Dragon Tree Conjecture asserts that for any integers kk and dd any graph with fractional arboricity at most k+dd+k+1k + \frac{d}{d+k+1} decomposes into k+1k+1 forests, such that for at least one of the forests, every connected component contains at most dd edges. We prove this conjecture when dk+1d \leq k+1. We also prove an approximate version of this conjecture, that is, we prove that for any positive integers kk and dd, any graph with fractional arboricity at most k+dd+k+1k + \frac{d}{d+k+1} decomposes into k+1k+1 forests, such that one for at least one of the forests, every connected component contains at most d+d(k(2dk+1+2)dk+1+2)k)k+1d + \frac{d(k (2\lceil \frac{d}{k+1} +2 \rceil)^{\lceil \frac{d}{k+1} + 2) \rceil} - k)}{k+1} edges.

Keywords

Cite

@article{arxiv.1909.07946,
  title  = {An Approximate Version of the Strong Nine Dragon Tree Conjecture},
  author = {Benjamin Moore},
  journal= {arXiv preprint arXiv:1909.07946},
  year   = {2020}
}

Comments

20 pages. The proof of Lemma 5.6 is inaccurate, as the legal order may change. As such, the proof fails. A recovery of this lemma (or something similar) would fix the proof. I am attempting to fix the error, but until then one should assume the result is incorrect

R2 v1 2026-06-23T11:18:12.991Z