#include <bits/stdc++.h> using namespace std; int n; vector<int> p; vector<pair<int, int>> e[10000002]; vector<int> fat, sz; int get(int x){ if(fat[x]==x) return x; return fat[x]=get(fat[x]); } int sol=0; void join(int a, int b, int c){ a=get(a), b=get(b); if(a==b) return; sol+=c; if(sz[a]<sz[b]) swap(a, b); sz[a]+=sz[b]; fat[b]=a; } int main(){ cin>>n; p.resize(n+1), fat.resize(n+1), sz.resize(n+1); for(int i=1;i<=n;++i) cin>>p[i], fat[i]=i, sz[i]=1; sort(p.begin()+1, p.end()); p.resize(unique(p.begin(), p.end())-p.begin()); n=p.size()-1; int m=p[n]; for(int i=1;i<=n;++i){ int j=i+1; for(int x=p[i];x<=m;x+=p[i]){ while(j<=n&&p[j]<x) j++; if(j<=n) e[p[j]%p[i]].push_back({i, j}); } } for(int i=0;i<=m;++i){ for(auto it:e[i]) join(it.first, it.second, i); } cout<<sol<<"\n"; return 0; }