#include <bits/stdc++.h>
using namespace std;
const int mod = 998244353;
inline int Mod(int x) { return x + ((x >> 31) & mod); }
inline int add(int x, int y) { return Mod(x + y - mod); }
inline int sub(int x, int y) { return Mod(x - y); }
inline int mul(int x, int y) { return 1ll * x * y % mod; }
const int maxn = 300000, K = 1200;
int f[K + 5][K], g[2][2 * maxn + 5];
int n, c;
inline int sum(int l, int r) { return (l + r) * (r - l + 1) / 2; }
inline int& G(int i, int j) { return g[i][j + n]; }
int main() {
	scanf("%d%d", &n, &c);
	int B = sqrt(2 * n);
	for (int i = 1; i <= n; i++) {
		int now = i % K;
		memset(f[now], 0, sizeof(f[now]));
		for (int j = 1; j <= i && (j <= B || sum(B, j) <= n); j++) {
			int lst = (i - j) % K;
			f[now][j] = add(j <= B && i == j, add(f[lst][j + 1], mul(c, f[lst][j - 1])));
		}
	}
	int ans = B < n;
	for (int i = 1; i <= B || sum(B, i) <= n; i++) ans = add(ans, f[n % K][i]);
	int now = 1, lst = 0;
	G(now, 0) = 1;
	for (int i = 2; i <= B; i++) {
		now ^= 1, lst ^= 1;
		memset(g[now], 0, sizeof(g[now]));
		for (int j = -sum(0, i - 1); j <= sum(0, i - 1); j++)
			G(now, j) = add(G(lst, j + i - 1), mul(c, G(lst, j - i + 1)));
		for(int j = B + 1; sum(j - i + 1, j) <= n; j++) ans = add(ans, G(now, n - j * i));
	}
	printf("%d", ans);
}