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Sum of all the numbers in the Nth row of the given triangle
  • Last Updated : 01 Apr, 2021

Given a positive integer N, the task is to find the sum of all the numbers in the Nth row of the below triangle. 
 


3 2 
6 2 3 
10 2 3 4 
15 2 3 4 5 
… 
… 
… 
 

Examples: 
 

Input: N = 2 
Output:
3 + 2 = 5
Input: N = 3 
Output: 11 
6 + 2 + 3 = 11 
 

 



Approach: Taking a closer look at the pattern, it can be observed that a series will be formed as 1, 5, 11, 19, 29, 41, 55, … whose Nth term is (N – 1) + N2.
Below is the implementation of the above approach: 
 

C++




// C++ implementation of the approach
#include <bits/stdc++.h>
using namespace std;
 
// Function to return the sum
// of the nth row elements of
// the given triangle
int getSum(int n)
{
    return ((n - 1) + pow(n, 2));
}
 
// Driver code
int main()
{
    int n = 3;
 
    cout << getSum(n);
 
    return 0;
}

Java




// Java implementation of the approach
class GFG
{
     
// Function to return the sum
// of the nth row elements of
// the given triangle
static int getSum(int n)
{
    return ((n - 1) + (int)Math.pow(n, 2));
}
 
// Driver code
public static void main(String[] args)
{
    int n = 3;
 
    System.out.println(getSum(n));
}
}
 
// This code is contributed by Code_Mech

Python3




# Python3 implementation of the approach
 
# Function to return the sum
# of the nth row elements of
# the given triangle
def getSum(n) :
 
    return ((n - 1) + pow(n, 2));
 
# Driver code
if __name__ == "__main__" :
 
    n = 3;
 
    print(getSum(n));
 
# This code is contributed by AnkitRai01

C#




// C# implementation of the approach
using System;
     
class GFG
{
     
// Function to return the sum
// of the nth row elements of
// the given triangle
static int getSum(int n)
{
    return ((n - 1) + (int)Math.Pow(n, 2));
}
 
// Driver code
public static void Main(String[] args)
{
    int n = 3;
 
    Console.WriteLine(getSum(n));
}
}
 
// This code is contributed by 29AjayKumar

Javascript




<script>
 
// Javascript implementation of the approach
 
// Function to return the sum
// of the nth row elements of
// the given triangle
function getSum(n)
{
    return ((n - 1) + Math.pow(n, 2));
}
 
// Driver code
var n = 3;
document.write(getSum(n));
 
</script>
Output: 
11

 

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