#include <bits/stdc++.h>
using namespace std;
bool ok(long long K, long long X){
  long long tv = 1000000000;
  long long fv = 0;
  while (tv - fv > 1){
    long long mid = (tv + fv) / 2;
    double prod = 1;
    prod *= mid;
    prod *= mid + K;
    if (prod > X * 2){
      tv = mid;
    } else {
      long long prod2 = 1;
      prod2 *= mid;
      prod2 *= mid + K;
      if (prod2 >= X){
        tv = mid;
      } else {
        fv = mid;
      }
    }
  }
  return tv * (tv + K) == X;
}
int main(){
  long long N, K, M;
  cin >> N >> K >> M;
  map<long long, int> mp;
  int B = 2;
  while (true){
    long long A = 1;
    while (true){
      double prod = 1;
      for (int i = 0; i <= B; i++){
        prod *= A + K * i;
      }
      if (prod > N * 2){
        break;
      }
      long long prod2 = 1;
      for (int i = 0; i <= B; i++){
        prod2 *= A + K * i;
      }
      if (prod2 > N){
        break;
      }
      mp[prod2]++;
      A++;
    }
    if (A == 1){
      break;
    }
    B++;
  }
  if (M >= 2){
    int ans = 0;
    for (auto P : mp){
      long long x = P.first;
      int cnt = P.second;
      if (cnt == M - 1 && ok(K, x) || cnt == M && !ok(K, x)){
        ans++;
      }
    }
    cout << ans << endl;
  } else {
    long long tv = 0;
    long long fv = 1000000000;
    while (fv - tv > 1){
      long long mid = (tv + fv) / 2;
      double prod = 1;
      prod *= mid;
      prod *= mid + K;
      if (prod > N * 2){
        fv = mid;
      } else {
        long long prod2 = 1;
        prod2 *= mid;
        prod2 *= mid + K;
        if (prod2 <= N){
          tv = mid;
        } else {
          fv = mid;
        }
      }
    }
    long long ans = tv;
    for (auto P : mp){
      long long x = P.first;
      int cnt = P.second;
      if (ok(K, x)){
        ans--;
      } else if (cnt == 1){
        ans++;
      }
    }
    cout << ans << endl;
  }
}