n, lower bound, upper bound

3 0 1
4 1 1
5 1 1
6 1 3
7 2 4
8 4 5
9 5 7
10 7 8
11 8 10
12 9 12
13 12 15
14 14 17
15 16 20
16 19 23
17 21 26
18 24 29
19 27 32
20 31 36