#include "iostream"
#include "climits"
#include "list"
#include "queue"
#include "stack"
#include "set"
#include "functional"
#include "algorithm"
#include "string"
#include "map"
#include "iomanip"
#include "random"

using namespace std;
const long long int MOD = 1000000007;
const long double EPS = 0.00000001;

long long int N, M, K, Q, W, H, L, R;
long long int ans;


int main() {
	ios::sync_with_stdio(false);
	cin >> N >> K >> Q;
	vector<int>dp(100001, INT_MAX);
	dp[1] = K;
	for (int i = 1; i < N; i++) {
		int box = i;
		for (int j = i * 2; j < N; j+=i) {
			dp[j] = min(dp[j], dp[i] + (int)K+(int)Q*(j - i) / i);
			box = j;
		}
		dp[box + i] = min(dp[box + i], dp[i] + (int)K + (int)Q*(box) / i);
	}
	ans = 100000000;
	for (int i = N; i < N * 2; i++)ans = min((int)ans, dp[i]-(int)K);
	cout << ans << endl;
	return 0;
}