- #1
Elbobo
- 145
- 0
Homework Statement
Write a C++ program to determine and print the sum of the series (1/3 + 1/6 + 1/9 + ... + 1/(3*n)) for a given value of n. In case you don't see the patter, the series can also be written as 1/(3*1) + 1/(3*2) +1/(3*3)+ ... + 1/(3*n). The value of n should be given interactively through the terminal. (You won't get credit if you do not use loops)
Homework Equations
[itex]Series = \frac{1}{3} \sum^{n}_{k=1} \frac{1}{k}[/itex]
The Attempt at a Solution
//The following code gives me a final answer of 0. I can't understand why my FOR loop doesn't work. Please help!
#include <iostream>
#include <cmath>
using namespace std;
int main( void )
{
int iN = 0;
int iK = 1;
cout << "Input a positive integer value for n for the summation of 1/(3k), from k=1 to k=n." << endl;
cin >> iN;
if(iN <= 0)
{
cout << "Invalid value for n. Exiting..." << endl;
return 0;
}
double dSum=0.0;
for(iK=1; iK <= iN; iK++)
{
dSum += double(1/iK);
}
cout << "The value of that summation is " << (1/3)*dSum << "." << endl;
return 1;
}