#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define inf 10e17
#define rep(i,n) for(long long i=0; i<n; i++)
#define repr(i,n,m) for(long long i=m; i<n; i++)
#define mod 1000000007
#define sorti(x) sort(x.begin(), x.end())
#define sortd(x) sort(x.begin(), x.end(), std::greater<long long>())
#define debug(x) std::cerr << (x) << std::endl;
#define roll(x) for (auto&& itr : x) { cerr << (itr) << " "; }

template <class T> inline void chmax(T &ans, T t) { if (t > ans) ans = t;}
template <class T> inline void chmin(T &ans, T t) { if (t < ans) ans = t;}

long long MOD(long long val, long long m) {
  long long res = val % m;
  if (res < 0) res += m;
  return res;
}

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

  ll ans = 0;
  rep(i, n) {
    ll tmp = MOD((sum[n] % mod) - (sum[i] % mod), mod);
    tmp *= f[i];
    tmp %= mod;
    ans += tmp;
    ans %= mod;
  }

  cout << ans << endl;
}