(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Give an example of a map from the set N of positive integers to itself which

is surjective but not injective.

2. Relevant equations

3. The attempt at a solution

It's easy to come up with an example, but I'm not sure on notation.

Here's how I've written it, but I know it's not quite right. I'm sure you can see the function that I am meaning to give. Any help with the notation would be appreciated. If it's not clear what function I mean, let me know and I will put it into words :)

[tex]\lbrace f:f(1)=1, f(s)=s-1,s>1\rbrace[/tex]

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# Homework Help: Function notation

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