#include "bits/stdc++.h"
using namespace std;
#define int long long
#define REP(i,n) for(int i = 0;i < (int)(n);i++)
#define RREP(i,n) for(int i = (int)n-1;i >= 0;i--)
#define FOR(i,s,n) for(int i = s;i < (int)n;i++)
#define RFOR(i,s,n) for(int i = (int)n-1;i >= s;i--)
#define ALL(a) a.begin(),a.end()
#define IN(a, x, b) (a<=x && x<b)
template<class T>inline bool CHMAX(T&a,T b){if(a<b){a = b;return true;}return false;}
template<class T>inline bool CHMIN(T&a,T b){if(a>b){a = b;return true;}return false;}
constexpr long long INF = 1e9,MOD = 1e9 + 7;


signed main(){
	int N,P;
	cin >> N >> P;
	int sum = 0,ans = 0;
	vector<int>dp(N);
	dp[0] = 0;
	dp[1] = 1;
	REP(i,N){
		if(i >= 2)(dp[i] = P * dp[i-1] + dp[i-2])%=MOD;
		(sum += dp[i])%=MOD;
		(ans += dp[i]*sum%MOD)%=MOD;
	}
	cout << ans << endl;
}