SET

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Let's consider some math problems.

JSZKC has a set A={1,2,...,N}A={1,2,...,N}. He defines a subset of AA as 'Meo set' if there doesn't exist two integers in this subset with difference one. For example, When A={1,2,3}, {1},{2},{3},{1,3}A={1,2,3},{1},{2},{3},{1,3} are 'Meo set'.

For each 'Meo set', we can calculate the product of all the integers in it. And then we square this product. At last, we can sum up all the square result of the 'Meo set'.

So please output the final result.

Input Format

The input file contains several test cases, each of them as described below.

• The first line of the input contains one integers NN (1 le N le 100)(1≤N≤100), giving the size of the set.

There are no more than 100100 test cases.

Output Format

One line per case, an integer indicates the answer.

样例输入

3

样例输出

23

题目来源

The 2018 ACM-ICPC China JiangSu Provincial Programming Contest

 

 

//JAVA 大数阶乘 
import java.io.*;
import java.math.BigInteger;
import java.util.*;

public class  Main
{
    public static void main(String args[])
    {
        Scanner cin = new Scanner(System.in);
int n;
while(cin.hasNext()){    
         n = cin.nextInt(); //输入int型 
        BigInteger ans = BigInteger.ONE;
       BigInteger a = BigInteger.ONE;
        for(int i = 1; i <= n+1; i++)
        ans = ans.multiply(BigInteger.valueOf(i));
        System.out.println(ans.subtract(a));
    }
}
}