Placement of quantifiers in a symbolic statement

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I have the statement:

Let $A_n$ be an indexed set of numbers defined by $A_n = n\mathbb{Z}_{\geq m}$ for $n,m \in \mathbb{Z}$. Consider the claim C: For all $n$, if $x,y$ is in $A_n$, then $x^{(y+1)}$ is in $A_n$.

I wrote C symbolically as the following.

$$C: \forall n, x,y \in A_n \implies x^{(y+1)} \in A_n.$$

Is this symbolic form correct? I feel like I need some separation between the universal quantifier and the rest of the statement. Thanks!

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Consider the claim C: For all $n$ , if $x,y$ is in $A_n$ , then $x^{(y+1)}$ is in $A_n$ .

Are the $x,y$ used here arbitrary ("any $x,y$...") or have they been defined earlier ("these $x,y$...")?

If they are predefined constants, then we have: $$\forall n\; \Big(n\in \Bbb Z\wedge x\in A_n\wedge y\in A_n \;\to\; x^{y+1}\in A_n\Big)$$


If they are arbitrary then you have to bind them to a quantified scope.

That is in full: $$\forall n\; \forall x\;\forall y\; \Big(n\in \Bbb Z\wedge x\in A_n\wedge y\in A_n \;\to\; x^{y+1}\in A_n\Big)$$

Or in abbreviated form:

$$\forall n\in\Bbb Z\; \forall x\in A_n\;\forall y\in A_n\; \bigl( x^{y+1}\in A_n\bigr)$$