Solution
= Solution
For a <monotone graph property> $P=(P_n)$, a function $p^*(n)$ is a <threshold function for a monotone graph property> when
$$
p/p^*\longrightarrow0
\quad\Longrightarrow\quad
\mathbb P(G(n,p)\in P_n)\longrightarrow0,
$$
and
$$
p/p^*\longrightarrow\infty
\quad\Longrightarrow\quad
\mathbb P(G(n,p)\in P_n)\longrightarrow1.
$$