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

#define int long long
#define rep(i, l, r) for (int i = (int)(l); i < (int)(r); i++)
#define all(x) (x).begin(), (x).end()
#define sz(x) ((int)x.size())
template <class T> bool chmax(T &a, T b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T> bool chmin(T &a, T b) {
  if (a > b) {
    a = b;
    return 1;
  }
  return 0;
}

/*
 */

using vi = vector<int>;
using vvi = vector<vi>;
using P = pair<int, int>;

const int mod = 1e9+7;

signed main() {
  int n, p;
  cin >> n >> p;

  vi a(n + 1);
  a[1] = 0;
  a[2] = 1;

  rep(i, 3, n + 1) {
    a[i] = (p*a[i-1]%mod + a[i-2])%mod;
  }

  int sum = 0, ans = 0;
  for(int i = n; i >= 1; i--){
    sum = (sum + a[i])%mod;
    ans = (ans + a[i]*sum%mod)%mod;
  }

  cout << ans << endl;

  return 0;
}