#include<bits/stdc++.h>

using namespace std;

#define F first
#define S second
#define L first
#define R second
#define X real()
#define Y imag()
#define pb push_back
#define pf push_front
#define cel(a, b) ((a) / (b) + ((a % b == 0) ? 0 : 1))

typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef complex<ld> point;

const int MAX = 1001000;

ll a, b;
ll f[MAX], n[MAX];
bool vis[MAX];

int main() {
    cin >> a >> b;
    for (ll i = 0; i <= b - a; i++)
        f[i] = 1, n[i] = i + a;
    for (ll p = 2; p * p <= b; p++) {
        if (vis[p])
            continue;
        for (ll x = p; x < MAX; x += p)
            vis[x] = true;
        for (ll x = cel(a, p) * p; x <= b; x += p) {
            ll &t = n[x - a], q = 1, s = 1;
            while (t % p == 0)
                t /= p, q *= p, s += q;
            f[x - a] *= s;
        }
    }
    for (ll i = 0; i <= b - a; i++) {
        if (n[i] != 1)
            f[i] *= 1ll + n[i];
    }
    ll ans = 0;
    for (ll i = 0; i <= b - a; i++)
        ans += f[i];
    cout << ans << endl;
    return 0;
}