This is a geometric sequence with the first term a = 48 and r = 1/4 = 0.25 as the common ratio. Since |r| < 1, this means that the terms are steadily getting smaller and smaller. The terms will approach 0 but not actually get there.
Note: if you added up all the terms of this infinite sequence, then the sum would be S = a/(1-r) = 48/(1-0.25) = 64
