你是否已经厌倦了计算随机数论函数的前缀和这类问题？作为一个变态的出题人，我在这里为你呈现了另一道不是题的题。
计算
$$\sum_{x=1}^{n} \text{lcm}(x, x + 1, \dots, x + k)$$
答案可能很大，请将其对 $10^9 + 7$ 取模后输出。
第一行包含两个整数 $n, k$ ($1 \le n \le 10^{18}, 0 \le k \le 30$)。
输出一个整数：答案。
10 3
18936
10000 6
43482752
1000000000 15
688102997
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