3 problems

Saks-West conjecture. In every product $P\times Q$ of two posets, the size of a largest semiantichain equals the size of a smallest unichain covering.

Dijoin weight decomposition conjecture. There exist weighted digraphs $(D,c)$ and $(D,c')$ such that

Let $G$ be a graph, and let $T$ be the set of its odd-degree vertices. A $T$-join is a subgraph whose odd-degree vertices are precisely the vertices in $T$, and a $T$-cut is a cut…