12, 18, 36, 102, 360?

The pattern of the number series is given as follows:
12 x 4 - 30 = 48 - 30 = 18
18 x 4 - 36 = 72 - 36 = 36
36 x 4 - 42 = 144 - 42 = 102
102 x 4 - 48 = 408 - 48 = 360
360 x 4 - 54 = 1440 - 54 = 1386