#include<bits/stdc++.h>
using namespace std;
const int mod=1e9+7;
typedef long long ll;
const int nmax=3;
ll fac[nmax],finv[nmax],inv[nmax];
 
void COMinit(){
  fac[0]=fac[1]=1;
  finv[0]=finv[1]=1;
  inv[1]=1;
  for(int i=2;i<nmax;i++){
    fac[i]=fac[i-1]*i%mod;
    inv[i]=mod-inv[mod%i]*(mod/i)%mod;
    finv[i]=finv[i-1]*inv[i]%mod;
  }
}
ll com(int n,int k){
  if(n<k||n<0||k<0){
    return 0;
  }
  return fac[n]*(finv[k]*finv[n-k]%mod)%mod;
}
int main(){
    ll n,p;cin >> n >> p;
    ll sum=0;
    vector<ll> a(n);
    a[0]=0;
    a[1]=1;
    for(int i=2;i<n;i++){
        a[i]=p*a[i-1]%mod+a[i-2];
        a[i]%=mod;
    }
    ll t=0;
    for(int i=0;i<n;i++){
        sum+=a[i];
        sum%=mod;
        t+=a[i]*a[i]%mod;
        t%=mod;
    }
    COMinit();
    cout << (sum*sum%mod+t)%mod*inv[2]%mod << endl;
}