#include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i = 0; i < (n);i++)
#define sz(x) int(x.size())
typedef long long ll;
typedef pair<int,int> P;
constexpr ll mod = 1e9+7;

int main(){
  int n;
  ll p;
  cin >> n >> p;
  map<int,ll> dp;  
  dp[1] = 0;
  dp[2] = 1;
  for (int i = 3; i <= n; i++) (dp[i] = p * dp[i-1] % mod + dp[i-2]) %= mod;
  ll res = 0;
  vector<ll> cum(n+1,0);
  rep(i,n) cum[i+1] = (cum[i] + dp[i+1]) % mod;
  for (int i = 1; i <= n; i++) (res += dp[i] * cum[i] % mod) %= mod;
  cout << res << endl;
  return 0;
}