#include<iostream>
#include<cmath>
#include<map>
#include<vector>
#include<set>
using namespace std;
long N,K,M;
map<long,long>cnt;
long count2()
{
	long L=0,R=1e9;
	while(R-L>1)
	{
		long mid=(L+R)/2;
		if(mid+K>N/mid)R=mid;
		else L=mid;
	}
	return L;
}
set<long>issq;
long A;
bool isok(long T)
{
	if(K>(int)1e8)
	{
		return issq.find(T)!=issq.end();
	}
	long V=K*K+4*T;
	long L=0,R=25e8;
	while(R-L>1)
	{
		long mid=(L+R)/2;
		if(mid*mid<=V)L=mid;
		else R=mid;
	}
	if(L*L!=V)return false;
	if((L-K)%2!=0)return false;
	long a=(L-K)/2;
	return a>=A;
}
main()
{
	cin>>N>>K>>M;
	A=1;
	for(;;A++)
	{
		if(A+K>N/A)break;
		long T=A;
		long U=A+K;
		int tm=0;
		while(U<=N/T)
		{
			T*=U;
			U+=K;
			cnt[T]++;
			tm++;
		}
		if(tm==1)
		{
			cnt[T]--;
			if(cnt[T]==0)cnt.erase(T);
			break;
		}
	}
	if(K>(int)1e8)
	{
		for(long a=A;;a++)
		{
			if(a+K>N/a)break;
			issq.insert(a*(a+K));
		}
	}
	long one=count2()-A+1;
	long ans=0;
	for(pair<long,long>p:cnt)
	{
		int now=p.second;
		if(isok(p.first))
		{
			one--;
			now++;
		}
		if(now==M)ans++;
	}
	cout<<ans+(M==1?one:0)<<endl;
}