#include <bits/stdc++.h>
using namespace std;
int l, r;
int dp[3000010], ans;
int c[3000010], n;
bool u[3000010];
int main() {
  int p, i, k;
  scanf("%d%d%d", &l, &r, &p);
  c[n++] = 1;
  for (k = 2; k < p; k++) {
    for (i = 2; i * i <= k; i++) {
      if (k % i == 0) {
        break;
      }
    }
    if (i * i <= k) continue;
    for (i = 0; i < n; i++) {
      if (1LL * c[i] * k <= r) {
        c[n++] = c[i] * k;
      }
    }
  }
  sort(c, c + n);
  for (i = 0; i < n; i++) dp[i] = p + 1;
  dp[0] = 0;
  u[0] = true;
  for (k = 1; k < p; k++) {
    for (i = 0; i < n; i++) dp[i]++;
    int x = 0;
    for (i = 0; i < n && 1LL * c[i] * k <= r; i++) {
      if (dp[i] < p) {
        while (c[x] < c[i] * k) x++;
        dp[x] = min(dp[x], dp[i] + 1);
        u[x] = true;
      }
    }
  }
  for (i = 0; i < n; i++)
    if (c[i] >= l && u[i]) ans++;
  printf("%d\n", ans);
  return 0;
}
