#include<bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<int,int> P;
ll const mod = 1e9+7;

#define p_ary(ary,a,b) do { cout << "["; for (int count = (a);count < (b);++count) cout << ary[count] << ((b)-1 == count ? "" : ", "); cout << "]\n"; } while(0)
#define p_map(map,it) do {cout << "{";for (auto (it) = map.begin();;++(it)) {if ((it) == map.end()) {cout << "}\n";break;}else cout << "" << (it)->first << "=>" << (it)->second << ", ";}}while(0)

int main() {
    int n;
    ll p;
    cin >> n >> p;
    vector<ll> a(n);
    a[0] = 0;
    a[1] = 1;
    for (int i = 2;i < n;++i) a[i] = (p*a[i-1]+a[i-2])%mod;
    ll sum = 0,ans = 0;
    for (int i = 0;i < n;++i) {
        (sum += a[i]) %= mod;
        (ans += a[i]*sum%mod) %= mod;
    }
    cout << ans << endl;
}