import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.Scanner;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        Scanner in = new Scanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        TaskA solver = new TaskA();
        solver.solve(1, in, out);
        out.close();
    }

    static class TaskA {
        public void solve(int testNumber, Scanner in, PrintWriter out) {
            int n = in.nextInt();
            int array[] = new int[n / 2];
            for (int i = 0; i < n / 2; i++) {
                array[i] = in.nextInt();
            }
            Arrays.sort(array);
            int answer1 = 0, answer2 = 0;
            for (int i = 0; i < n / 2; i++) {
                answer1 += Math.abs(array[i] - (i * 2 + 1));
                answer2 += Math.abs(array[i] - (i * 2 + 2));
            }
            out.print(Math.min(answer1, answer2));
        }

    }
}

