#include<iostream>
#include<vector>
#include<algorithm>
using namespace std;

#define ll long long
const ll INF = 1e18;
const int MAXN = 2 * 1e5 + 5;
int n;
ll p, q, f[MAXN];

int main(){
	freopen("money.in", "r", stdin);
	freopen("money.out", "w", stdout);
    ios::sync_with_stdio(0);
    cin.tie(0);
    
    cin >> n >> p >> q;

	for(int i = 1;i <= n;i ++) f[i] = INF;

    f[0] = 0;

    for(int i = 1;i <= n;++ i){
        f[i] = f[i - 1] + q;
        for(int j = 1;j <= i;++ j){
            ll c, cnt = p * j * j;
            if(i == j){
                c = cnt;
            }
			else{
                c = f[i - j - 1] + q + cnt;
            }
            if(c < f[i]) f[i] = c;
            if(cnt > f[i]) break;
        }
    }
    cout << f[n] << '\n';
    return 0;
}