This has occured 23 times
Once. They went to the NCAA tournament for the first time in 2012 as a #15 seed.
5
13
Yes.In fact,in the 2013 NCAA men's basketball tournament, the #12 seed beat the #5 seed in three of the four regionals:California over UNLV 64-61 in the East; Oregon over Oklahoma State 68-55 in the Midwest; and Mississippi over Wisconsin 57-46 in the West.
Yes it has happened 2 times in 1986 and 1997
1 seed
UNC was a number 1 seed in the 2009 NCAA basketball tournament.
3
A 4 seed.
The lowest seed to make it to the Sweet 16 in the NCAA basketball tournament this year was a 15th seed.
Wake Forest was a number 4 seed in the 2009 NCAA Basketball Tournament.