Proving that $\limsup {x_{n}} = \lim_{n \rightarrow \infty} ( \sup _ {m \geq n} x_{m} )$.
I want to prove it using only the definition of the $\limsup {x_{n}}$: that $\limsup {x_{n}}$ is the largest accumulation point of $\{x_{n}\}$.
I have seen many links for the proof here but as far as I understand not directly from this definition and after reading them all I got confused, could any one help me in proving this?