#include <cstdio>
#include <iostream>

using namespace std;

long long n;
long long p;
long long q;
long long res = 1e18;

int main () {
	
	freopen ("money.in", "r", stdin);
	freopen ("money.out", "w", stdout);
	
	cin >> n >> p >> q;
	
	for (int i = 1; i <= n; i++) {
		long long ans = i * q;
		int j = n - i;
		int place = i + 1;
		if (j <= place) {
			ans += j * p;
		}
		else {
			long long num = j / place;
			if (j % place) {
				ans += (place - 1) * p * num * num + p * (j - (place - 1) * num) * (j - (place - 1) * num);
			}
			else {
				ans += place * p * num * num;
			}
		}
		res = min (res, ans);
	}
	cout << res << endl;
	
	return 0;
}