Modulo Sum of Increasing Sequences

AtCoder
IDarc145_f
Time4000ms
Memory256MB
Difficulty
Find the number, modulo $998244353$, of non-decreasing sequences $A=(A_1,A_2,\ldots,A_N)$ of length $N$ consisting of integers between $0$ and $M$ (inclusive) that satisfy the following, for each $K=0,1,\ldots,\mathrm{MOD}-1$: * the sum of the elements in $A$ is congruent to $K$ modulo $\mathrm{MOD}$. What is a non-decreasing sequence? A sequence $B$ is non-decreasing if and only if $B_i \leq B_{i+1}$ for every integer ($1 \le i \le |B| - 1$), where $|B|$ is the length of $B$. ## Constraints * $1 \leq N ,M\leq 10^6$ * $1\leq \mathrm{MOD}\leq 500$ * All values in input are integers. ## Input Input is given from Standard Input in the following format: $N$ $M$ $\mathrm{MOD}$ [samples]
Samples
Input #1
2 2 4
Output #1
2 1 2 1

There are $6$ non-decreasing sequences of length $2$ consisting of integers between $0$ and $2$: $(0, 0), (0, 1),(0,2), (1,1),(1,2),(2,2)$. Here, we have:

*   $2$ sequences whose sums are congruent to $0$ modulo $4$: $(0,0),(2,2)$;
    
*   $1$ sequence whose sum is congruent to $1$ modulo $4$: $(0,1)$;
    
*   $2$ sequences whose sums are congruent to $2$ modulo $4$: $(0,2),(1,1)$;
    
*   $1$ sequence whose sum is congruent to $3$ modulo $4$: $(1,2)$.
Input #2
3 45 3
Output #2
5776 5760 5760
Input #3
1000000 1000000 6
Output #3
340418986 783857865 191848859 783857865 340418986 635287738

Print the counts modulo $998244353$.
API Response (JSON)
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      "content": "Find the number, modulo $998244353$, of non-decreasing sequences $A=(A_1,A_2,\\ldots,A_N)$ of length $N$ consisting of integers between $0$ and $M$ (inclusive) that satisfy the following, for each $K=0",
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      "statement_type": "Markdown",
      "content": "Find the number, modulo $998244353$, of non-decreasing sequences $A=(A_1,A_2,\\ldots,A_N)$ of length $N$ consisting of integers between $0$ and $M$ (inclusive) that satisfy the following, for each $K=0...",
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