#include<bits/stdc++.h>
using namespace std;
#include <atcoder/all>
using namespace atcoder;
using mint=modint1000000007;
using ll=long long;
using pp=pair<ll,ll>;
#define sr string 
#define vc vector
#define fi first
#define se second
#define rep(i,n) for(ll i=0;i<(ll)n;i++)
#define pb push_back
#define all(v) v.begin(),v.end()
#define pque priority_queue
#define bpc(a) __builtin_popcount(a)
int main(){
  int n;cin>>n;
  int d=sqrt(n); d=max(d,2);
  vc dp(n,vc<mint>(d,0)); 
  vc<mint>dx(n,0); dx[0]=1;
  rep(i,n){
    int a;cin>>a;
    rep(j,d)dx[i]+=dp[i][j];
    dx[i+1]+=dx[i];
    if(a>=d)for(int j=i+a;j<n;j+=a)dx[j]+=dx[i];
    else{
      if(a>1)dp[i][a]+=dx[i];
      else if(i+2<n)dp[i+2][1]+=dx[i];      
    }
    rep(j,d)if(i+j<n)dp[i+j][j]+=dp[i][j];
  }
  cout<<dx[n-1].val();
}