Thresholds and Expectation Thresholds

(See e.g. [2], [6] or [18]. Of course p0(n) is not quite unique, but following common practice we will often say “the” threshold when we should really say “a.”) It follows from [8] that every {Fn} has a threshold, and that in fact (see e.g. [18, Proposition 1.23 and Theorem 1.24]) p0(n) := pc(Fn) is a threshold for {Fn}. So the quantity pc conveniently captures threshold behavior, in particular allowing us to dispense with sequences.