#include <bits/stdc++.h>
#define int long long
#define ls(s) (int)s.size()
#define pb push_back
#define pp pop_back
#define ff first
#define ss second
#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(),v.rend()
#define rep(i,a,b) for(int i = a;i<=b;++i)
#define tr(it,v) for(auto &it:v)
using namespace std;
const int N = 1e6+5;
bool dp[N];
int a[N];
int b[N];
signed main(){
// ios::sync_with_stdio(false);cin.tie(nullptr);
int n;
cin >> n;
for(int i = 1;i<=n;++i) cin >> a[i];
for(int i = 1;i<=n;++i) cin >> b[i];
int ans = 0;
for(int i = 1;i<=n;++i){
ans += b[i];
if(i != 1){
ans -= (min(a[i-1],a[i]) / lcm(a[i-1]/b[i-1],a[i]/b[i]));
}
}
cout << ans + n + 2;
return 0;
}
