Score : 1000 points
Takahashi and Aoki are going to together construct a sequence of integers.
First, Takahashi will provide a sequence of integers a, satisfying all of the following conditions:
Then, Aoki will perform the following operation an arbitrary number of times:
How many sequences a can be obtained after this procedure, modulo 10^9+7?
The input is given from Standard Input in the following format:
N K
Print the number of the sequences a that can be obtained after the procedure, modulo 10^9+7.
4 2
6
The following six sequences can be obtained:
1 10
10
6 3
75
1000000000 1000000000
875699961