#include<bits/stdc++.h>
using namespace std;
#define int long long
int f[25][25][25], a, b, c;
int w(int a, int b, int c) {
	if(a <= 0 || b <= 0 || c <= 0) return 1;
	if(a > 20 || b > 20 || c > 20) return w(20, 20, 20);
	if(f[a][b][c] != 0) return f[a][b][c];
	if(a < b && b < c) {
		return f[a][b][c] = w(a, b, c - 1) + w(a, b - 1, c - 1) - w(a, b - 1, c);
	}
	else {
		return f[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);
	}
}
signed main() {
	while(cin >> a >> b >> c) {
		if(a == -1 && b == -1 && c == -1) {
			return 0;
		}
		cout << "w(" << a << "," << b << "," << c << ") = " << w(a, b, c) << endl;
	}
	return 0;
}