We define $$$x \bmod y$$$ as the remainder of division of $$$x$$$ by $$$y$$$ ($$$\%$$$ operator in C++ or Java, mod operator in Pascal).
Let's call an array of positive integers $$$[a_1, a_2, \dots, a_k]$$$ stable if for every permutation $$$p$$$ of integers from $$$1$$$ to $$$k$$$, and for every non-negative integer $$$x$$$, the following condition is met:
That is, for each non-negative integer $$$x$$$, the value of $$$(((x \bmod a_1) \bmod a_2) \dots \bmod a_{k - 1}) \bmod a_k$$$ does not change if we reorder the elements of the array $$$a$$$.
For two given integers $$$n$$$ and $$$k$$$, calculate the number of stable arrays $$$[a_1, a_2, \dots, a_k]$$$ such that $$$1 \le a_1 < a_2 < \dots < a_k \le n$$$.
The only line contains two integers $$$n$$$ and $$$k$$$ ($$$1 \le n, k \le 5 \cdot 10^5$$$).
Print one integer — the number of stable arrays $$$[a_1, a_2, \dots, a_k]$$$ such that $$$1 \le a_1 < a_2 < \dots < a_k \le n$$$. Since the answer may be large, print it modulo $$$998244353$$$.
7 3
16
3 7
0
1337 42
95147305
1 1
1
500000 1
500000
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