THT bac giang

//Nguyen Huu Hoang Minh
#include <bits/stdc++.h>
#define sz(x) int(x.size())
#define all(x) x.begin(),x.end()
#define reset(x) memset(x, 0,sizeof(x))
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define N 1000005
#define remain(x) if (x > MOD) x -= MOD
#define ii pair<int, int>
#define iiii pair< ii , ii >
#define viiii vector< iiii >
#define vi vector<int>
#define vii vector< ii >
#define bit(x, i) (((x) >> (i)) & 1)
#define Task "test"
#define int long long

using namespace std;

typedef long double ld;
const int Mod = 1000000007;
const int minf = -1e10;
const int MM = 1ll*Mod*Mod;
const int base = 101;

int l, r;
int ispr[N];
map<int,int> d;
vector<int> prim;

int has(vector<int> s)
{
    int dh = 0;
    for(auto x : s)
    {
        dh = (dh*base + x) %Mod;
    }
    return dh;
}

void init(int x)
{
    vector<int> v;
    for(auto y : prim)
    {
        if (y > x) break;
        if (x%y==0)
            v.pb(y);
    }
    d[has(v)]++;
}

void readfile()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);cout.tie(0);
    if (fopen(Task".inp","r"))
    {
        freopen(Task".inp","r",stdin);
        //freopen(Task".out","w",stdout);
    }
    cin >> l >> r;
    memset(ispr, 1, sizeof ispr);
    ispr[1] = ispr[0] = 0;
    for(int i=2; i*i <= r; i++)
    {
        if (ispr[i])
        {
            for(int j = i*i; j<=N; j+=i) ispr[j] = 0;
        }
    }
    for(int i=2; i<=r; i++) if (ispr[i]) prim.pb(i);
    for(int i=l; i<=r; i++)
    {
        init(i);
    }
}

int C(int n, int k)
{
    int tu = 1;
    for(int i=n-k+1; i<=n; i++) tu *= i;
    return tu/2;
}

void proc()
{
    int res = 0;
    for(auto it = d.begin(); it != d.end(); it++)
    {
        int val = it->se;
        if (val >= 2) res += C(val,2);
    }
    cout << res;
}

signed main()
{
    readfile();
    proc();
    return 0;
}