Given a number N. The task is to find the sum of below series upto nth term.
3, 7, 13, 21, 31, ….
Examples:
Input : N = 3 Output : 23 Input : N = 25 Output : 5875
Approach:
Subtracting the above two equations, we have:
Below is the implementation of the above approach:
C++
// C++ Program to find the sum of given series#include <iostream>#include <math.h>using namespace std;// Function to calculate sumint findSum(int n){ // Return sum return (n * (pow(n, 2) + 3 * n + 5)) / 3;}// Driver codeint main(){ int n = 25; cout << findSum(n); return 0;} |
Java
// Java program to find sum of// n terms of the given seriesimport java.util.*; class GFG { static int calculateSum(int n) { // returning the final sum return (n * ((int)Math.pow(n, 2) + 3 * n + 5)) / 3; } // Driver Code public static void main(String arr[]) { // number of terms to // find the sum int n = 25; System.out.println(calculateSum(n)); } } // This code is contributed // by Surendra_Gangwar |
Python 3
# Python program to find the # sum of given series# Function to calculate sumdef findSum(n): # Return sum return (n*(pow(n, 2)+3 * n + 5))/3# driver coden = 25print(int(findSum(n))) |
C#
// C# program to find // sum of n terms of // the given seriesusing System;class GFG { static int calculateSum(int n) { // returning the final sum return (n * ((int)Math.Pow(n, 2) + 3 * n + 5)) / 3; } // Driver Code public static void Main() { // number of terms to // find the sum int n = 25; Console.WriteLine(calculateSum(n)); } } // This code is contributed // by inder_verma. |
PHP
<?php// PHP Program to find the// sum of given series// Function to calculate sumfunction findSum($n){ // Return sum return ($n * (pow($n, 2) + 3 * $n + 5)) / 3;}// Driver code$n = 25;echo findSum($n);// This code is contributed // by inder_verma?> |
Javascript
<script>// javascript program to find sum of// n terms of the given series function calculateSum(n) { // returning the final sum return (n * (parseInt(Math.pow(n, 2) + 3 * n + 5)) / 3); } // Driver Code // number of terms to // find the sumvar n = 25; document.write(calculateSum(n)); // This code contributed by shikhasingrajput </script> |
5875
Time Complexity : O(1)
Auxiliary Space: O(1)
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