/* -*- coding: utf-8 -*-
 *
 * 3388.cc:  No.3388 Sum of Function - yukicoder
 */

#include<cstdio>
#include<vector>
#include<algorithm>

using namespace std;

/* constant */

/* typedef */

using vb = vector<bool>;
using vi = vector<int>;

/* global variables */

vb primes;
vi pnums;

/* subroutines */

int gen_primes(int maxp) {
  primes.assign(maxp + 1, true);
  primes[0] = primes[1] = false;

  int p;
  for (p = 2; p * p <= maxp; p++)
    if (primes[p]) {
      pnums.push_back(p);
      for (int q = p * p; q <= maxp; q += p) primes[q] = false;
    }
  for (; p <= maxp; p++)
    if (primes[p]) pnums.push_back(p);
  return (int)pnums.size();
}

int f(int x) { return x * x * x - x * x + x + 1; }

/* main */

int main() {
  int a, b;
  scanf("%d%d", &a, &b);

  gen_primes(b);

  int sum = 0;
  for (auto p: pnums)
    if (a <= p && p <= b) sum += f(p);

  printf("%d\n", sum);
  
  return 0;
}