Symbolizing Definition of Cauchy Sequence with Predicate Logic

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I am trying to symbolize the following definition of a Cauchy Sequence with the syntax of predicate logic. Can someone please take a look and tell me if I am symbolizing the definition correctly according to the syntax of predicate logic?

Definition: "The sequence $\{a_n\}$ is a Cauchy Sequence if for all $\epsilon > 0$, there exists a number $Z$ such that $m,n > Z \implies |a_m -a_n| < \epsilon$."

I came up with the following symbolization key:

UD: The set of all sequences, terms of sequences and real numbers.

$Sx$: x is a sequence

$Tx,y$: x is a real number term of y

$Nx$: x is a natural number

$Rx$: x is a real number

$Gx,y$: x is greater than y

$Lx,y$: x is less than y

$A_x$: |x|

$Cx$: x is a Cauchy Sequence

$0$: $0$ as a constant

Using the key above, here is my attempt at symbolizing it into predicate logic syntax:

$(\forall s)(\forall a)(\forall n)(\forall m)[((Ss \wedge Ta,s) \wedge (Nn \wedge Nm) ) \wedge ((\forall \epsilon)(\exists z)[((G\epsilon,0 \wedge Rz) \wedge (Gmz \wedge Gnz)) \implies LA_{a_m-a_n}, \epsilon]) \Leftrightarrow Cs]$

Would my symbolized sentence be a correct interpretation of the definition of a Cauchy Sequence?