#include<bits/stdc++.h>
#define REP(i,n) for(int i=0,i##_len=int(n);i<i##_len;++i)
#define rep(i,a,b) for(int i=int(a);i<int(b);++i)
#define All(x) (x).begin(),(x).end()
#define rAll(x) (x).rbegin(),(x).rend()
using namespace std;
using ll = long long;

int main(){
    ll mod=1e9+7;
    ll N,p;
    cin>>N>>p;
    vector<ll> a(N);
    a[0]=0,a[1]=1;
    rep(i,2,N){
        a[i]=p*a[i-1]+a[i-2];
        a[i]%=mod;
    }
    vector<ll> S(N+1);
    REP(i,N){
        S[i+1]=S[i]+a[i];
        S[i+1]%=mod;
    }
    ll ans=0;
    REP(i,N){
        ans+=a[i]*S[i+1];
        ans%=mod;
    }
    cout<<ans<<endl;
}