 Hilbert cube

A Hilbert $n$-cube in the positive integers is a setwhere $a,x_1,\dots ,x_n$ are positive integers.

The Hilbert cube is a mathematical construct that serves as a model for certain topological concepts. Specifically, the Hilbert cube is defined as the topological space \( [0, 1]^{\mathbb{N}} \), which is the infinite product of the closed interval \([0, 1]\) in the real numbers.