google-deepmind / google-deepmind/formal-conjectures
Erdős Problem 993
Open
ams-05: Combinatorics
erdos-problems
new conjecture
- Dominant language
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Description
### What is the conjecture
https://www.erdosproblems.com/993
The independent set sequence of any tree or forest is unimodal.
In other words, if $i_k(G)$ counts the number of independent sets of vertices of size $k$ in a graph $G$, and $T$ is any tree or forest, then for some $m\geq 0$
$$i_{0}(T)\leq i_{1}(T)\leq\cdots\leq i_{m}(T)\geq i_{m+1}(T)\geq i_{m+2}(T)\geq\cdots.$$
Status: open
### Choose either option
- [ ] I plan on working on this conjecture
- [x] This issue is up for grabs: I would like to see this conjecture added by somebody else
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Assessment
This issue has not been assessed yet.