Abstract:

We prove that the ordinary generating function of Bell numbers satisfies no algebraic differential equation  over C(x) (in fact, over a larger field). We investigate related numbers counting various set partitions (the Uppuluri-Carpenter numbers, the numbers of partitions with j mod i blocks,  the Bessel numbers, the numbers of connected partitions, and the numbers of crossing partitions) and prove for their ogf's analogous results. Recurrences, functional equations, and continued fraction expansions are derived.