AtCoder Regular Contest 116
C
Multiple Sequences
AtCoder
⌀ 1468
原题
← BD →
翻译中…

Problem Statement

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Given are integers $N$ and $M$. How many sequences $A$ of $N$ integers satisfy the following conditions?

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  • $1 \leq A_i \leq M \left(i = 1, 2, \ldots, N\right)$
  • $A_{i+1}$ is a multiple of $A_i$. $\left(i = 1, 2, \ldots, N - 1\right)$
翻译中…

Since the answer can be enormous, report it modulo $998244353$.

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Constraints

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  • All values in input are integers.
  • $1 \leq N \leq 2 \times 10^5$
  • $1 \leq M \leq 2 \times 10^5$
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Input

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Input is given from Standard Input in the following format:

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N M

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Output

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Print the answer.

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样例

Input #1
3 4
Output #1
13
Some of the sequences $A$ satisfying the conditions follow: - $A = \left(1, 1, 4\right)$ - $A = \left(3, 3, 3\right)$ - $A = \left(1, 2, 4\right)$
Input #2
20 30
Output #2
71166
Input #3
200000 200000
Output #3
835917264
题目信息
题号
arc116_c
时间限制
2 s
内存限制
1024 MB

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