2 problems

A $3$-graph is linear if any two distinct edges have at most one vertex in common. A $3$-graph $F$ is layered if there is a function $f:V(F)\to\mathbb N$ satisfying the source's la…

A $3$-graph $F$ is layered if there is a function $f:V(F)\to\mathbb N$ such that: every edge has exactly one vertex whose label is strictly greater than the other two; edges with t…