程序来找到系列0、3 / 1、8 / 3、15 / 5……的N个项。

给定数字N ，任务是找到以下系列的第N个项。

0, 3/1, 8/3, 15/5…… 
 

例子：

Input:  n=4
Output: 15/5

Input: n=3
Output: 8/3

方法：通过清楚地检查序列，我们可以找到该序列的Tn项，并且在tn的帮助下，我们可以找到所需的结果。

Tn=0 + 3/1 +8/3 +15/5……. 
We can see that here odd terms are negative and even terms are positive 
Tn=((n²-1)/(2*n-3)) 
 

下面是上述方法的实现。

CPP

// C++ implementation of the approach
#include 
using namespace std;
 
// Function to return the nth term of the given series
void Nthterm(int n)
{
 
    // nth term
    int numerator = pow(n, 2) - 1;
    int denomenator = 2 * n - 3;
    cout << numerator << "/" << denomenator;
}
 
// Driver code
int main()
{
    int n = 3;
 
    Nthterm(n);
 
    return 0;
}

Python

# Python3 implementation of the approach 
    
# Function to return the nth term of the given series 
def Nthterm(n): 
    
    # nth term 
    numerator = n**2-1
    denomenator = 2 * n-3
     
    print(numerator, "/", denomenator)
    
    
# Driver code 
n = 3
Nthterm(n)

Java

// Java implementation of the approach
import java.util.*;
import java.lang.*;
import java.io.*;
 
public class GFG {
 
    // Function to return the nth term of the given series
    static void NthTerm(int n)
    {
        int numerator
            = ((int)Math.pow(n, 2)) - 1;
        int denomeanator = 2 * n - 3;
        System.out.println(numerator + "/" + denomeanator);
    }
 
    // Driver code
    public static void main(String[] args)
    {
        int n = 3;
        NthTerm(n);
    }
}

C#

// C# implementation of the approach
using System;
public class GFG {
 
    // Function to return the nth term of the given series
    static void NthTerm(int n)
    {
 
        int numerator
            = ((int)Math.Pow(n, 2)) - 1;
        int denomeanator = 2 * n - 3;
        Console.WriteLine(numerator + "/" + denomeanator);
    }
 
    // Driver code
    public static void Main()
    {
        int n = 3;
        NthTerm(n);
    }
}

Javascript

 
// javascript implementation of the approach
 
 
// Function to return the nth term of the given series
function Nthterm( n)
{
 
    // nth term
    let numerator = Math.pow(n, 2) - 1;
    let denomenator = 2 * n - 3;
     document.write( numerator + "/" + denomenator);
}
 
// Driver code
let n = 3;
 
    Nthterm(n);
 
// This code contributed by gauravrajput1
 

输出：

8/3