Fibonacci Java Program: Complete Program for Fibonacci Series

Updated on February 20, 2013

Java Program for Fibonacci Series

Fibonacci is the sequence of number, which has 2 forms, first is the sequence that begins in 0 and the second form is the sequence that begins in 1. After the constants, the following number is the sum of the first 2 previous numbers. For example:

The constants in Fibonacci Series are:

Fib0 = 0;

Fib1 = 1;

Fib2 = 2;

So, if the next sequence is the sum of the first 2 numbers in the sequence, then, Fib3, Fib4 and Fib5 will be:

Fib3 = Fib1 + Fib2;

Fib4 = Fib2 + Fib3;

Fib5 = Fib3 + Fib4;

And so onâ€¦

Thus, Fibonacci Series is easy to predict if you know its rules of sequences. It is also easy to program in Java.

Fib0
Fib1
Fib2
Fib3
Fib4
Fib5
Fib6
Fib7
Fib8
0
1
1
2
3
5
8
13
21

Example Fibonacci Series of Number 10

Fib0
Fib1
Fib2
Fib3
Fib4
Fib5
Fib6
Fib7
Fib8
Fib9
Fib10
0
1
1
2
3
5
8
13
21
34
55

Fibonacci Java Program Algorithm:

The Java Program for Fibonacci that will be given here is to look for the Fibonacci series of the number that will be entered by the user. Example: 8, the program should return the numbers shown in the Fibonacci series of the number 8 above. The program would test the number 8 and number 10 and let us see if it returns the same as shown on the table.

Java Source Code for Fibonacci Series

```// packageName: fib

package fib;

import java.util.Scanner;

public class Main
{

public static void main(String[] args)
{
Scanner input = new Scanner(System.in);
System.out.print("Enter a number: ");
int entered_num= input.nextInt();

System.out.println("The Fibonacci Sequence of the Number " + entered_num + " is:");

int constant1 = 1;
int constant2= 1;
int nextNumber = 0;
int count=0;

for (int i=0;i<=entered_num;i++)
{
System.out.println("F" + count + "=" + nextNumber);
constant1 = constant2;
constant2 = nextNumber;
nextNumber = constant1 + constant2;
count++;
}

}

}
```

Sample Output:

It works! Check and trace the code on how the program works. Try it on your Java IDE. Happy Programming!

0

12

4

0

2

10

4