It is not possible; but there is a very easy solution. Rename your files as follows
link_2.html instead of 2.html
link_3.html instead of 3.html
and just update your code to
<a href="link_2.html"> Link 2</a><br/>
<a href="link_3.html"> Link 3</a><br/>
What they click on save file name it will come up as Link_2.html or Link 2.html dependent on the browser used.
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