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C++ program to print Lucas series upto N terms

Here, we are going to implement a C++ program to print Lucas series upto N terms.
Submitted by Aditi S., on May 30, 2019

Given N and we have to print lucas series upto N terms.

Lucas series

The Lucas series is an integer series very similar to the Fibonacci series, named after the French mathematician François Édouard Anatole Lucas. Each term of the Lucas series is defined as the sum of the previous two terms of the series with the first two terms being 2 and 1 respectively. The Lucas series and Fibonacci series are complementary to each other. The terms of the series are integer powers of the golden ratio rounded to the closest whole number. Given below is the code to find the Terms of the Lucas series up to n iterations.

Code

/*Program to print the Lucas series for n terms.*/

#include <iostream>
using namespace std;

int main()
{
	int n, i, t1 = 2, t2 = 1, tn;
	cout << "Enter the number of terms desired in the lucas series: ";
	cin >> n;
	
	if (n == 1)
		cout << endl << 2 << endl;
	else if (n == 2)
		cout << endl << 2 << endl << 1 << endl;
	else if (n > 2)
	{
		cout <<endl<<"Lucas series for "<< n<< " terms is:"<<endl<< t1 << endl << t2 << endl;
		for (i = 0; i < n-2; i++)
		{
			tn = t1 + t2;
			cout << tn << endl;
			t1 = t2;
			t2 = tn;

		}
	}

	return 0;
}

Output

First run:
Enter the number of terms desired in the lucas series: 5

Lucas series for 5 terms is:
2
1
3
4
7

Second run:
Enter the number of terms desired in the lucas series: 10

Lucas series for 10 terms is:
2
1
3
4
7
11
18
29
47
76