Problem Statement
Snuke has a die (singular of dice) that shows integers from $1$ through $N$ with equal probability, and an integer $1$.
He repeats the following operation while his integer is less than or equal to $M$.
- He rolls the die. If the die shows an integer
$x$, he multiplies his integer by$x$.
Find the expected value of the number of times he rolls the die until he stops, modulo $10^9+7$.
Definition of the expected value modulo $10^9+7$ We can prove that the desired expected value is always a rational number. Moreover, under the constraints of the problem, when the value is represented as an irreducible fraction $\frac{P}{Q}$, we can also prove that $Q \not\equiv 0 \pmod{10^9+7}$. Thus, an integer $R$ such that $R \times Q \equiv P \pmod{10^9+7}$ and $0 \leq R \lt 10^9+7$ is uniquely determined. Answer such $R$.
Constraints
$2 \leq N \leq 10^9$$1 \leq M \leq 10^9$
Input
Input is given from Standard Input in the following format:
N M
Output
Print the answer.
样例
2 1
2
2 39
12
3 2
250000004
2392 39239
984914531
1000000000 1000000000
776759630
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