public class ForPowerB {
    public static void main(String[] args) {
        int base = 2;
        int maxx = 10;
        int sum = 0;
        int powr = 1;
        for (int i = 0; i < maxx; i++) {
            sum += powr;
            powr *= base;
        }
        System.out.println(sum);
    }
}