How do you express "Every pair of integer has a greatest common divisor" in mathematical terms?

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How do you express "All pairs of integer have a greatest common divisor" in mathematical term?

My answer

This is what I came up with but I'm unsure if it's right.

Any help is appreciated, thanks!

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A correct statement is:

$$\forall x,y\left(\exists d\left(d\mid x\land d\mid y\land\forall e\left((e\mid x\land e\mid y)\Rightarrow e\leq d\right)\right)\right) $$

This is only true if your language is the positive integers.

If the language includes zero you need something like:

$$\forall x,y\left((x=0\land y=0)\lor\\\exists d\left(d\mid x\land d\mid y\land\forall e\left((e\mid x\land e\mid y)\Rightarrow e\leq d\right)\right)\right) $$