Erdős Problem 552

## What is the conjecture

https://www.erdosproblems.com/552

Determine the Ramsey number
$$R(C_4,S_n),$$
where $S_n$ is the star on $n+1$ vertices.

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

Start by reading the Erdős Problems 552 statement at erdosproblems.com/552 and reviewing how this repository represents formalized conjectures in Lean. The work is complete when the open conjecture about R(C₄,Sₙ) is added as a formal Lean statement with the repository's expected supporting metadata and checks.

Written by the indexing model from the issue text.