#include <bits/stdc++.h>
using namespace std;
int main(){
	int N, M;
	cin >> N >> M;
	vector<vector<int>> A(N + 1);
	for (int i = 1; i <= N; i++){
		for (int j = i; j <= N; j += i){
			A[j].push_back(i);
		}
	}
	long long ans = 0, sum = 0;
	for (int x = 1; x <= N; x++){
		sum += M;
		for (int i : A[x]){
			sum -= i;
		}
		ans = max(ans, sum);
	}
	cout << ans << endl;
}