I am studying program analysis and synthesis, I was reading a presentation about some DFA analysis.
I can't seem to understand why $$\bigcap_{s'\in\text{pred (s)}}\text{Out}(s')$$ and $$\operatorname{Gen}(s)\cup(\operatorname{In}(s)\setminus \operatorname{Kill}(s))$$ is monotone, as claimed in slide 22.
I don't even understand exactly what is the function that is claimed to be monotone. Can anyone please help ? any help is greatly appreciated!