#P5106. dkw的lcm

dkw的lcm

Problem Description

In particular, the LCM of a single number is the number itself.

Kind dkw decides to tell you the statement directly:

$$\prod_{i_1=1}^n\prod_{i_2=1}^n …\prod_{i_k=1}^n \varphi\big(lcm(i_1,i_2,…,i_k)\big)$$

Please compute the expression above, and output the answer modulo 109+710^9+7.

Here, lcm(i1,i2,...,ik)lcm(i_1,i_2,...,i_k) denotes the least common multiple of these kk numbers.

Here, φ\varphi denotes Euler's totient function.

Here, ∏\prod denotes the product symbol, which is the multiplicative version of ∑\sum.

Input Format

Two positive integers, n,kn,k.

Output Format

One non-negative integer, representing the value of the expression modulo 109+710^9+7.

2 2
1

Hint

For 50% of the testdata, 1≤n,k≤81\le n,k\le 8.

For 100% of the testdata, 1≤n,k≤1061\le n,k\le 10^6.

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