Java: Display first 10 lucus numbers

Last update on March 11 2025 11:10:12 (UTC/GMT +8 hours)

First 10 Lucas Numbers

Write a Java program to display the first 10 lucus numbers.

The Lucas numbers or series are an integer sequence named after the mathematician François Édouard Anatole Lucas, who studied both that sequence and the closely related Fibonacci numbers. Lucas numbers and Fibonacci numbers form complementary instances of Lucas sequences.
The sequence of Lucas numbers is: 2, 1, 3, 4, 7, 11, 18, 29, ….

Sample Solution:

Java Code:

import java.util.Scanner;
public class Example7 {
   public static void main(String[] args) { 

     System.out.print("\nFirst ten Lucas a numbers: "); 
     int n = 10;
     int n1 = 2, n2 = 1, n3;
        if (n > 1){
            System.out.println("\n2\n1");
            for(int i = 2; i < n; ++i){
                n3 = n2;
                n2 += n1;
                n1 = n3;
                System.out.println(n2);
            }
        }
        else if (n == 1)
            System.out.println("\n2");

        else
            System.out.println("Input a positive number.");
    }
 }

Sample Output:

First ten Lucas a numbers:                                                                                    
2                                                                                                  
1                                                                                                  
3                                                                                                  
4                                                                                                  
7                                                                                                  
11                                                                                                  
18                                                                                                  
29                                                                                                  
47                                                                                                  
76

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Java program to compute Lucas numbers using recursion with memoization for efficiency.
• Write a Java program to generate Lucas numbers iteratively and then print them in reverse order.
• Write a Java program to compute the ratio of consecutive Lucas numbers and analyze their convergence.
• Write a Java program to compare Lucas and Fibonacci numbers by outputting their differences for the first 10 terms.

Java Code Editor:

Contribute your code and comments through Disqus.

Previous: Write a Java program to generate and show the first 15 narcissistic decimal numbers.
Next: Write a Java program to print out the first 10 Catalan numbers by extracting them from Pascal's triangle.