#include <iostream>
#include <vector>

using namespace std;

long long modulo = 998244353;

long long binaryExponentiation(long long value, long long power) {
    vector<long long> powers(31);
    powers[0] = value;
    for (int i = 1; i <= 30; i++) {
        powers[i] = powers[i - 1] * powers[i - 1];
        powers[i] %= modulo;
    }
    long long answer = 1;
    for (int i = 0; i <= 30; i++) {
        if ((power & (1 << i)) > 0) {
            answer *= powers[i];
            answer %= modulo;
        }
    }
    return answer;
}

long long divide(long long a, long long b) {
    // find a/b mod modulo
    // find b ^ (modulo - 2)
    long long inverse = binaryExponentiation(b, modulo - 2);
    return ((inverse * a) % modulo);
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int n, k;
    cin >> n >> k;
    long long answer = n + 1;
    for (int i = 0; i < k; i++) {
        answer *= n;
        answer %= modulo;
    }
    if (answer % 2 == 0) {
        answer /= 2;
    } else {
        answer = (answer + modulo) / 2;
    }
    if (k % 2 == 1) {
        cout << answer << "\n";
    } else {
        long long factorial1 = 1;
        for (int i = (k/2) + 1; i <= k; i++) {
            factorial1 *= i;
            factorial1 %= modulo;
        }
        long long factorial2 = 1;
        for (int i = 1; i <= (k/2); i++) {
            factorial2 *= i;
            factorial2 %= modulo;
        }
        long long combination = factorial1;
        combination = divide(combination, factorial2);

        long long value = 0;
        for (int i = 1; i < n; i++) {
            long long tmp = binaryExponentiation(i, k/2);
            tmp *= binaryExponentiation(n - i, k/2);
            tmp %= modulo;
            tmp *= combination;
            tmp %= modulo;
            value += tmp;
            value %= modulo;
        }
        if (value % 2 == 0) {
            value /= 2;
        } else {
            value = (value + modulo) / 2;
        }
        answer -= value;
        answer %= modulo;
        if (answer < 0) {
            answer += modulo;
        }
        cout << answer << "\n";
    }
    return 0;
}