using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace yuki_407
{
    class Program
    {
        static void Main(string[] args)
        {
            var a = scan();
            int max = a[1]/(a[0]-1);
            var k = Enumerable.Range(2, max).ToList();
            eratos(k, max);
            long ans = 0;
         
            foreach (var i in k)
            {
                //Console.WriteLine(i);
                int m = a[1] - i*(a[0]-1) + 1;
                if (m<0)
                {
                    break;
                }
                else
                {
                    ans += m;
                }
            }
            Console.WriteLine(ans);
        }
        static void eratos(List<int> p,int n)
        {
            for (int i = 0; i < p.Count; i++)
            {
                int t = p[i];

                for (int j = t+t; j <= n; j+=t)
                {
                    p.Remove(t);
                }
                
            } 
        }
        static int[] scan()
        {
            return
                Array.ConvertAll
                (Console.ReadLine().Split(' '), int.Parse);
        }
    }
}