http://www.sportsclubstats.com/NHL.html
This is also a good resource for finding out how many wins a team needs to clinch the playoffs.

What they do is simulate every remaining game of the season, and then run the simulation 32 million times. A team is declared "in" the playoffs if none of those simulations show them missing the playoffs ...

So technically these are not the same as magic numbers; when a team is declared in the playoffs, what that really means is "according to our model, their probability of missing the playoffs is less than 1 in 32 million".

The exact formula used to determine the probability of a team winning a game isn't clearly documented, so take it for what it's worth.