#D11451. Sum of gcd of Tuples (Hard)
Sum of gcd of Tuples (Hard)
Sum of gcd of Tuples (Hard)
Consider sequences \{A_1,...,A_N\} of length N consisting of integers between 1 and K (inclusive).
There are K^N such sequences. Find the sum of \gcd(A_1, ..., A_N) over all of them.
Since this sum can be enormous, print the value modulo (10^9+7).
Here \gcd(A_1, ..., A_N) denotes the greatest common divisor of A_1, ..., A_N.
Constraints
- 2 \leq N \leq 10^5
- 1 \leq K \leq 10^5
- All values in input are integers.
Input
Input is given from Standard Input in the following format:
N K
Output
Print the sum of \gcd(A_1, ..., A_N) over all K^N sequences, modulo (10^9+7).
Examples
Input
3 2
Output
9
Input
3 200
Output
10813692
Input
100000 100000
Output
742202979
inputFormat
input are integers.
Input
Input is given from Standard Input in the following format:
N K
outputFormat
Output
Print the sum of \gcd(A_1, ..., A_N) over all K^N sequences, modulo (10^9+7).
Examples
Input
3 2
Output
9
Input
3 200
Output
10813692
Input
100000 100000
Output
742202979
样例
100000 100000
742202979