题解 | #尼科彻斯定理#

import java.util.Scanner;

// 等差数列是数学家解法，暴力才是王道 亲们
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int m = in.nextInt();
        int sum = m * m * m;
        if (m == 1) {
            System.out.print("1");
        }
        for (int i = 1; i < sum; i = i + 2) {
            int next = i;
            int dp = i;
            for (int j = 0; j < m; j++) {
                next = next+2;
                dp = dp + next;
                if (dp == sum) {
                    StringBuffer sb = new StringBuffer("");
                    for (int k = i; k <= next; k = k + 2) {
                        sb.append(k);
                        if (k != next) {
                            sb.append("+");
                        }
                    }
                    System.out.print(sb.toString());
                    return;
                }
            }   
        }
    }
}