Solution
= Solution
By <Poisson thinning>, allocating a Poisson$(365)$ population independently and uniformly among $365$ days gives independent Poisson$(1)$ counts. Hence
$$
\boxed{\mathbb P(Z_1=z_1,\ldots,Z_{365}=z_{365})
=e^{-365}\prod_{i=1}^{365}\frac1{z_i!},
\qquad z_i\in\mathbb Z_{\geq0}.}
$$