Lambert series and Liouville's identities
The relationship between Liouville’s arithmetic identities and products of Lambert series is investigated. For example it is shown that Liouville’s arithmetic formula for the sum , where n ∈ ℕ and F: ℤ → ℂ is an even function, is equivalent to the Lambert series for (θ ∈ ℝ, |q| < 1) given by Ramanujan.