#include <iostream>
#include <vector>
#include <cmath>
#include <map>
#include <set>
#include <iomanip>
#include <queue>
#include <algorithm>
#include <numeric>
#include <deque>

using namespace std;

const long long m = 1e9+7;

long long mod_exp(long long b, long long e){
    if (e > 0 && b == 0) return 0;
    long long ans = 1;
    b %= m;

    while (e > 0){
        if ((e & 1LL)) ans = (ans * b) % m;
        e = e >> 1LL;
        b = (b*b) % m;
    }

    return ans;
}

//

int main(){

    long long N, K;
    cin >> N >> K;
    K %= m;

    cout << (m+mod_exp(K*(K+3)/2, N)-mod_exp(K*(K+1)/2, N))%m << endl;

    return 0;
}