#include <cstdio>
#include <iostream>

#define N int(1e7 + 5)

using namespace std;

bool sq_full[N];

int main() {
    freopen("sqfree.in", "r", stdin);
    freopen("sqfree.out", "w", stdout);

    int k, a, b;
    cin >> k >> a >> b;

    for (int i = 2; i * i <= b; i++) {
        for (int j = 1; j * i * i <= b; j++) {
            sq_full[j * i * i] = true;
        }
    }

    for (int i = a; ; i++) {
        if (!sq_full[i]) k--;
        if (!k) {
            cout << i << endl;
            return 0;
        }
    }

    return 0;
}