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I wonder if there is an isomorphism between the group of [itex]\mathbb{N}[/itex] and the group of [itex]\mathbb{Q}[/itex] (or [itex]\mathbb{Q}+[/itex]). I know there is a proof that there is a bijection between these sets, but I didn't find a way how to construct the isomorphism.

What confuses me a little is that (I think) the group of natural numbers has only one generator, while the group of (positive) rationals has more than one generator, so I can't see how the mapping would look like.

Thank you for any hints!

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# Is there a isomorphism between N and Q?

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