Proposition 1: shrinking $S$ with $x(\delta(S)) \le 2$ and $x(\delta(R)) \ge 2$ for all $R \subset S$ is safe

Initializing...

Proposition 1: shrinking $S$ with $x(\delta(S)) \le 2$ and $x(\delta(R)) \ge 2$ for all $R \subset S$ is safe · Prove2Me