A real sequence ( x n ) n ∈ N {\displaystyle {}{\left(x_{n}\right)}_{n\in \mathbb {N} }} is called decreasing, if x n + 1 ≤ x n {\displaystyle {}x_{n+1}\leq x_{n}} holds for all n ∈ N {\displaystyle {}n\in \mathbb {N} } .
