Problems
Gardener-painter
Gardener-painter
Gardener has to paint trees after planting. He has paint of three colour: white, blue and orange.
How many ways he can paint of N
trees, if not any two the same colours can be side by side?
Input
The quantity of trees is N
(1 ≤ N ≤ 50
).
Output
The quantity of ways of paint.
Input example #1
3
Output example #1
12