#include<bits/stdc++.h>
using namespace std;
long long ans[25][25][25];

long long w(long long a,long long b,long long c){
	if(a<=0||b<=0||a<=0)return 1;
	if(a>20||b>20||c>20)return w(20,20,20);
	if(ans[a][b][c]!=0)return ans[a][b][c];
	if(a<b&&b<c){
		ans[a][b][c]=w(a,b,c-1)+w(a,b-1,c-1)-w(a,b-1,c);
		return ans[a][b][c];
	}
	ans[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 ans[a][b][c];
}
int main(){
	long long a,b,c;
	while(true){
		scanf("%lld%lld%lld", &a, &b, &c);
		if(a==-1&&b==-1&&c==-1)break;
		long long ans=w(a,b,c);
		printf("w(%lld, %lld, %lld)= %lld\n", a, b, c, w(a,b,c));
	}
	return 0;
}