Question

Write the program in Java to find the sum of the following series:

S = 1 + (1 + 2) + (1 + 2 + 3) + ........................ + (1 + 2 + 3 + ........................ + n)

Answer 1

import java.util.*;
public class Q2c
{ public static void main(String arg[])
{int n, tmp = 0, sum = 0;
Scanner obj = new Scanner(System.in);
System.out.println("Enter the value of n....no. of terms");
n = obj.nextInt();
for (int i = 1; i <= n; i++)
{ tmp = 0; // reset to zero for each value of i
for (int j = 1; j <= i; j++)
tmp = tmp + j; // i = 4, tmp = (1 + 2 + 3 + 4)
sum = sum + tmp; 
}
System.out.println("Sum of the Series = " + sum);
}}