#include <bits/stdc++.h>
using namespace std;
typedef long long LL;
const int MAXN = 20000007;

namespace ModCalculator {
    const int MOD = 998244353;
    inline void Inc(int &x, int y) {
        x += y; if (x >= MOD) x -= MOD;
    }
    inline int Add(int x, int y) {
        Inc(x, y); return x;
    }
    inline void Dec(int &x, int y) {
        x -= y; if (x < 0) x += MOD;
    }
    inline int Sub(int x, int y) {
        Dec(x, y); return x;
    }
    inline int Mul(int x, int y) {
        return 1LL * x * y % MOD;
    }
    inline int Ksm(int x, int y) {
        int ret = 1;
        for (; y; y >>= 1) {
            if (y & 1) ret = Mul(ret, x);
            x = Mul(x, x);
        }
        return ret;
    }
    inline int Inv(int x) {
        return Ksm(x, MOD - 2);
    }
}
using namespace ModCalculator;

int n, m, fac[MAXN], finv[MAXN];

inline int C(int x, int y) {
    return Mul(fac[x], Mul(finv[y], finv[x - y]));
}

inline int Coef(int x, int y) {
    return C(y + x - 1, x - 1);
}

void solve() {
    scanf("%d %d", &n, &m);
    int mx = n * 2;
    fac[0] = 1;
    for (int i = 1; i <= mx; ++i) {
        fac[i] = Mul(fac[i - 1], i);
    }
    finv[mx] = Inv(fac[mx]);
    for (int i = mx; i >= 1; --i) {
        finv[i - 1] = Mul(finv[i], i);
    }
    int ans = 0;
    for (int k = 0; ; ++k) {
        int i = (3 * k * k - k) / 2;
        if (i >= m) break;
        int cur = Coef(n + 1, m - 1 - i);
        (k & 1)? Dec(ans, cur) : Inc(ans, cur);
    }
    for (int k = -1; ; --k) {
        int i = (3 * k * k - k) / 2;
        if (i >= m) break;
        int cur = Coef(n + 1, m - 1 - i);
        ((-k) & 1)? Dec(ans, cur) : Inc(ans, cur);
    }
    printf("%d\n", Mul(ans, finv[n]));
}

int main() {
    solve();
    return 0;
}