For me it was questionable whether there's a way to get Google presentations linked directly. Every time after publishing your presentation, you simply receive an URL to view your presentation online, but the problem is, if you go to that URL to view the presentation online, Google requires you to log in to your account. The question is how you can view your presentation online without being logged in, so everyone can view your presentation online.
The simple trick is appending "&skipauth=true" to the URL provided by Google and replace "Presentation" with "Present" as with this example:
Here's an URL provided by Google. Just make sure, you're not logged in to your Google account, so will see that clicking on this URL will launch you to that page where you have to log in.
This is the same URL but replaced as it has been explained above, so added the key "&skipauth=true" to end of the URL by replacing "Presentation" with "Present".
There's also a way to download the presentation and it's just replacing "MiscCommands?command=saveasdoc&exportFormat=ppt&" with "Presentation?" like this URL:
Read more on Google OS.