程序以找到系列0、4、14、30、51、80、114、154、200，…的N个项

给定数字N。任务是编写一个程序来查找以下系列的第N个术语：

0, 4, 14, 30, 51, 80, 114, 154, 200, …(N Terms)

例子：

Input: N = 4
Output: 82
For N = 4
4th Term = ( 4 * 4 - 2 * 4 + 2) 
         = 10

Input: N = 10
Output: 122

方法：本系列的广义第N个术语：

$nth\: Term\: of\: the\: series\: = n^2-2n+2$

以下是所需的实现：

C++

// CPP program to find the N-th term of the series:
// 5, 10, 17, 26, 37, 50, 65, 82, ...
#include 
#include 
using namespace std;
 
// calculate Nth term of series
int nthTerm(int n)
{
    return pow(n, 2) - 2 * n + 2;
}
 
// Driver Function
int main()
{
    int N = 4;
 
    cout << nthTerm(N);
 
    return 0;
}

Java

// Java program to find the N-th term of the series:
// 5, 10, 17, 26, 37, 50, 65, 82, ...
import java.util.*;
 
class solution
{
 
// calculate Nth term of series
static int nthTerm(int n)
{
     
    //return the total sum
    return (int)Math.pow(n, 2) - 2 * n + 2;
}
 
//Driver function
public static void main(String arr[])
{
    int N = 4;
 
    System.out.println(nthTerm(N));
 
}
 
}

Python3

# Python3 program to find the N-th
# term of the series:
# 0, 4, 14, 30, 51, 80, 114, 154, 200, …
 
# from math lib. import everything
from math import *
 
# calculate Nth term of series
def nthTerm(n) :
     
    return pow(n, 2) - 2 * n + 2
 
         
# Driver code    
if __name__ == "__main__" :
 
    N = 4
    print(nthTerm(N))
 
# This code is contributed by
# ANKITRAI1

C#

// C# program to find the
// N-th term of the series:
// 5, 10, 17, 26, 37, 50, 65, 82, ...
using System;
 
class GFG
{
 
// calculate Nth term of series
public static int nthTerm(int n)
{
 
    // return the total sum
    return (int)Math.Pow(n, 2) -
                    2 * n + 2;
}
 
// Driver Code
public static void Main(string[] arr)
{
    int N = 4;
 
    Console.WriteLine(nthTerm(N));
}
}
 
// This code is contributed
// by Shrikant13

Javascript

// JavaScript program to find the N-th term of the series:
// 5, 10, 17, 26, 37, 50, 65, 82, ...
 
// calculate Nth term of series
function nthTerm( n)
{
    return Math.pow(n, 2) - 2 * n + 2;
}
// Driver code
 
    let N = 4;
   document.write( nthTerm(N) );
 
// This code contributed by aashish1995
 

输出：

10

时间复杂度： O(1)