#include <bits/stdc++.h>
using namespace std;
long long x,y,z;
long long w(long long a,long long b,long long c){
	if(a<=0 || b<=0 || c<=0){
		return 1;
	}else if(a>20 || b>20 ||c>20){
		return w(20,20,20);
	}else if(a<b && b<c){
		return w(a,b,c-1)+w(a,b-1,c-1)+w(a,b-1,c);
	}else{
		return w(a-1,b,c)+w(a-1,b-1,c)+w(a-1,b,c-1)-w(a-1,b-1,c-1);
	}
}
int main(){
	while(1){
		cin>>x>>y>>z;
		if(x!=-1 && y!=-1 && z!=-1){
			cout<<"w("<<x<<","<<y<<","<<z<<") = "<<w(x,y,z)<<endl;
		}else{
			return 0;
		}
	}
	return 0;
}