#include<iostream>
#include<string>
#include<iomanip>
#include<cmath>
#include<vector>
#include<algorithm>

using namespace std;

#define int long long
#define endl "\n"

constexpr long long INF = (long long)1e18;
constexpr long long MOD = 1'000'000'007; 

string yn(bool f){return f?"Yes":"No";}
string YN(bool f){return f?"YES":"NO";}



signed main(){
	cin.tie(nullptr);
	ios::sync_with_stdio(false);
	cout<<fixed<<setprecision(10);
	
	int N, p;
	vector<int> a;
	int sum = 0, ans = 0;
	
	cin>>N>>p;
	
	a.resize(N);
	
	a[0] = 0;
	a[1] = 1;
	
	for(int i = 2; i < N; i++){
		a[i] = a[i-1] * p + a[i-2];
		a[i] %= MOD;
	}
	
	for(int i = 0; i < N; i++){
		sum += a[i];
		sum %= MOD;
		
		ans += a[i] * sum;
		ans %= MOD;
	}
	
	cout<<ans<<endl;
	
	return 0;
}