#include <bits/stdc++.h>
using namespace std;
template <typename T, typename U>
inline void smin(T &a, U b) {
  if (a > b) a = b;
}
template <typename T, typename U>
inline void smax(T &a, U b) {
  if (a < b) a = b;
}
template <typename T>
inline void gn(T &first) {
  char c, sg = 0;
  while (c = getchar(), (c > '9' || c < '0') && c != '-')
    ;
  for ((c == '-' ? sg = 1, c = getchar() : 0), first = 0; c >= '0' && c <= '9';
       c = getchar())
    first = (first << 1) + (first << 3) + c - '0';
  if (sg) first = -first;
}
template <class T, class T1>
inline void gn(T &first, T1 &second) {
  gn(first);
  gn(second);
}
template <class T, class T1, class T2>
inline void gn(T &first, T1 &second, T2 &z) {
  gn(first);
  gn(second);
  gn(z);
}
template <typename T>
inline void print(T first) {
  if (first < 0) {
    putchar('-');
    return print(-first);
  }
  if (first < 10) {
    putchar('0' + first);
    return;
  }
  print(first / 10);
  putchar(first % 10 + '0');
}
template <typename T>
inline void println(T first) {
  print(first), putchar('\n');
}
template <typename T>
inline void printsp(T first) {
  print(first), putchar(' ');
}
template <class T, class T1>
inline void print(T first, T1 second) {
  printsp(first), println(second);
}
template <class T, class T1, class T2>
inline void print(T first, T1 second, T2 z) {
  printsp(first), printsp(second), println(z);
}
int power(int a, int b, int m, int ans = 1) {
  for (; b; b >>= 1, a = 1LL * a * a % m)
    if (b & 1) ans = 1LL * ans * a % m;
  return ans;
}
int L, R, k;
int p[111], pk;
void prime() {
  for (int i = 2; i < k; i++) {
    int ok = 1;
    for (int j = 2; j < i; j++)
      if (i % j == 0) ok = 0;
    if (ok) p[pk++] = i;
  }
}
int num[3000000], d[3000000], ok[3000000], n;
void find(int n, int cur) {
  if (cur == pk) {
    if (n <= R) num[::n++] = n;
    return;
  }
  find(n, cur + 1);
  if ((long long)n * p[cur] <= R) find(n * p[cur], cur);
}
int main() {
  gn(L, R, k);
  prime();
  find(1, 0);
  for (int i = 0; i < n; i++) d[i] = 0x3f3f3f3f;
  d[0] = 0;
  sort(num, num + n);
  for (int i = 2; i < k; i++) {
    for (int j = 0, nj = 0;; j++) {
      long long v = num[j] * i;
      while (nj < n && num[nj] < v) nj++;
      if (nj == n) break;
      if (d[nj] > d[j] + 1) {
        d[nj] = d[j] + 1;
        if (d[nj] + i <= k) ok[nj] = 1;
      }
    }
  }
  int ans = 0;
  for (int i = 0; i < n; i++)
    if (num[i] >= L && ok[i]) ans++;
  println(ans);
  return 0;
}
