#include<iostream>
#include<string>
#include<queue>
#include<vector>
#include<cassert>
#include<random>
#include<set>
#include<map>
#include<cassert>
#include<unordered_map>
#include<bitset>
#include<numeric>
#include<algorithm>
using namespace std;
typedef long long ll;
const int inf=1<<30;
const ll INF=1LL<<62;
typedef pair<int,ll> P;
typedef pair<int,P> PP; 
const ll MOD=998244353;
const int dy[]={0,1,0,-1};
const int dx[]={1,0,-1,0};

int main(){
    ll N,M;
    cin>>N>>M;
    ll ans=0;
    ll x=min(N,M-1);
    for(int i=1;i<=M;i++){
        ans+=x%i;
    }
    cout<<ans<<endl;
}