#include<bits/stdc++.h>
using namespace std;
long long int e,f,g;
long long int w(long long int a,long long int b,long long int 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>>e>>f>>g;
	if(e!=-1&&f!=-1&&g!=-1)
    cout<<"w("<<e<<","<<f<<","<<g<<")="
	<<w(e,f,g)<<"\n";
	else break;
    }
	return 0;
}