Erdős Problem 612

### What is the conjecture

https://www.erdosproblems.com/612

Let $G$ be a connected graph with $n$ vertices, minimum degree $d$, and diameter $D$. Show if that $G$ contains no $K_{2r}$ and $(r-1)(3r+2)\mid d$ then
$$D\leq \frac{2(r-1)(3r+2)}{2r^2-1}\frac{n}{d}+O(1),$$
and if $G$ contains no $K_{2r+1}$ and $3r-1 \mid d$ then
$$D\leq \frac{3r-1}{r}\frac{n}{d}+O(1).$$

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