using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;

namespace No407{
    public class Program{
        public static void Main(string[] args){
            var sr = new StreamReader();
            //---------------------------------
            var N = sr.Next<long>();
            var L = sr.Next<long>();

            if(L == 1){
                Console.WriteLine(0);
                return;
            }

            Console.WriteLine(Primes((int)L - 1).Sum(p => Math.Max(L - p * (N - 1) + 1, 0)));
            //---------------------------------
        }

        //from http://qiita.com/gushwell/items/5d3988a2f5de0587c88f------------------
        public static IEnumerable<int> Primes(int maxnum){
            var sieve = new BitArray(maxnum + 1, true);
            int squareroot = (int)Math.Sqrt(maxnum);
            for(int i = 2; i <= squareroot; i++) {
                if(sieve[i] == false)
                    continue;
                for(int n = i * 2; n <= maxnum; n += i)
                    sieve[n] = false;
                if(sieve[i])
                    yield return i;
            }
            for(int i = squareroot + 1; i <= maxnum; i++)
                if(sieve[i] == true)
                    yield return i;
        }
        //---------------------------------------------------------------------------
    }

    public class StreamReader{
        private readonly char[] _c = {' '};
        private int _index = -1;
        private string[] _input = new string[0];

        public T Next<T>(){
            if(_index == _input.Length - 1){
                _index = -1;
                while(true){
                    string rl = Console.ReadLine();
                    if(rl == null){
                        if(typeof(T).IsClass) return default(T);
                        return (T)typeof(T).GetField("MinValue").GetValue(null);
                    }
                    if(rl != ""){
                        _input = rl.Split(_c, StringSplitOptions.RemoveEmptyEntries);
                        break;
                    }
                }
            }
            return (T)Convert.ChangeType(_input[++_index], typeof(T), System.Globalization.CultureInfo.InvariantCulture);
        }

        public T[] Next<T>(int x){
            var ret = new T[x];
            for(var i = 0; i < x; ++i) ret[i] = Next<T>();
            return ret;
        }

        public T[][] Next<T>(int y, int x){
            var ret = new T[y][];
            for(var i = 0; i < y; ++i) ret[i] = Next<T>(x);
            return ret;
        }
    }
}