#include<bits/stdc++.h> 
#define ll long long
using namespace std;
ll s[50][50][50];
ll w(ll a,ll b,ll c){
	if(a<=0||b<=0||c<=0){
		return 1;
	}else if(a>20||b>20||c>20){
		s[a][b][c]=w(20,20,20);
	}else if(a<b&&b<c){
		s[a][b][c]=w(a,b,c-1)+w(a,b-1,c-1)-w(a,b-1,c);
	}else{
		s[a][b][c]=w(a-1,b,c)+w(a-1,b-1,c)+w(a-1,b,c-1)-w(a-1,b-1,c-1);
	}
	return s[a][b][c];
}
int main(){	
	ll a1,b1,c1;
	while(1){
		cin>>a1>>b1>>c1;
		if(a1==-1&&b1==-1&&c1==-1){
			break;
		}else{
			cout<<"w(1, 1, 1) = "<<w(a1,b1,c1)<<endl;
		}
	}
	return 0;
}