#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const ll mod = 998244353;
const int N = 200005;
const int INF = 0x3f3f3f3f;
int add(int a, int b) {
    a += b;
    if (a >= mod) a -= mod;
    return a;
}
ll mul(ll a, ll b) {
    return (a % mod) * (b % mod) % mod;
}
using Vec = vector<int>;
using Mat = vector<Vec>;
Mat mat_mul(const Mat &A, const Mat &B) {
    int D = A.size();
    Mat C(D, Vec(D));
    for (int i = 0; i < D; i++) {
        for (int k = 0; k < D; k++) {
            if (A[i][k]) {
                ll av = A[i][k];
                for (int j = 0; j < D; j++) {
                    if (B[k][j]) {
                        C[i][j] = (C[i][j] + av * B[k][j]) % mod;
                    }
                }
            }
        }
    }
    return C;
}
Vec mat_vec_mul(const Mat &A, const Vec &v) {
    int D = A.size();
    Vec res(D);
    for (int i = 0; i < D; i++) {
        ll sum = 0;
        for (int j = 0; j < D; j++) {
            if (A[i][j] && v[j]) {
                sum += (ll)A[i][j] * v[j];
                if (sum >= (1LL << 62)) sum %= mod;
            }
        }
        res[i] = int(sum % mod);
    }
    return res;
}
Vec apply_pow(Mat M, ll exp, Vec v) {
    int D = M.size();
    Vec res = v;
    while (exp) {
        if (exp & 1) res = mat_vec_mul(M, res);
        M = mat_mul(M, M);
        exp >>= 1;
    }
    return res;
}
int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    ll K, L, R;
    cin >> K >> L >> R;
    int k = (int)K;
    int D = 1 + 1 + (k + 1) + 1;
    int ida = 0;
    int ide = 1;
    int idq = 2;
    int ids = 2 + (k + 1);
    vector<vector<int>> C(k + 1, vector<int>(k + 1));
    for (int i = 0; i <= k; i++) {
        C[i][0] = C[i][i] = 1;
        for (int j = 1; j < i; j++) C[i][j] = add(C[i - 1][j - 1], C[i - 1][j]);
    }
    Mat M(D, Vec(D));
    M[ida][ida] = (int)(K % mod);
    M[ida][ide] = 1;
    M[ida][idq + k] = 1;
    M[ide][ide] = (int)(K % mod);
    for (int j = 0; j <= k; j++) {
        for (int i = 0; i <= j; i++) {
            M[idq + j][idq + i] = C[j][i];
        }
    }
    M[ids][ids] = 1;
    M[ids][ida] = (int)(K % mod);
    M[ids][ide] = 1;
    M[ids][idq + k] = 1;

    Vec v0(D);
    v0[ida] = 1;
    v0[ide] = 1;
    v0[idq + 0] = 1;
    for (int i = 1; i <= k; i++) v0[idq + i] = 0;
    v0[ids] = 1;
    auto get_sum = [&](ll x) {
        if (x < 0) return 0LL;
        Vec v = apply_pow(M, x, v0);
        return (ll)v[ids];
    };
    ll res = (get_sum(R) - get_sum(L - 1)) % mod;
    if (res < 0) res += mod;
    cout << res << "\n";
    return 0;
}