Write Java Program to Print Fibonacci Series upto N Number

In mathematics, the Fibonacci numbers or Fibonacci series or Fibonacci sequence are the numbers in the following integer sequence:  

By definition, the first two numbers in the Fibonacci sequence are 0 and 1, and each subsequent number is the sum of the previous two.
In mathematical terms, the sequence F_n of Fibonacci numbers is defined by the recurrence relation

with seed values

Here is a simplest Java Program to generate Fibonacci Series.

package com.crunchify.tutorials;

 

import java.util.Scanner;

 

/**

* @author Crunchify.com

*/

public class CrunchifyFibonacci {

 

    @SuppressWarnings("resource")

    public static void main(String args[]) {

 

        //input to print Fibonacci series upto how many numbers

        System.out.print("Enter number upto which Fibonacci series to print: ");

        int number = new Scanner(System.in).nextInt();

 

        System.out.println("\n\nFibonacci series upto " + number +" numbers : ");

        //printing Fibonacci series upto number

        for(int i=1; i<=number; i++){

            System.out.print(fibonacciRecusion(i) +" ");

        }

    }

 

    // Java program for Fibonacci number using recursion.

    public static int fibonacciRecusion(int number){

        if(number == 1 || number == 2){

            return 1;

        }

 

        return fibonacciRecusion(number-1) + fibonacciRecusion(number -2); //tail recursion

    }

 

    // Java program for Fibonacci number using Loop.

    public static int fibonacciLoop(int number){

        if(number == 1 || number == 2){

            return 1;

        }

        int fibo1=1, fibo2=1, fibonacci=1;

        for(int i= 3; i<= number; i++){

            fibonacci = fibo1 + fibo2; //Fibonacci number is sum of previous two Fibonacci number

            fibo1 = fibo2;

            fibo2 = fibonacci;

 

        }

        return fibonacci; //Fibonacci number

    }    

}

Output:

Output of ICrunchFibonacci.java

1 2 3 4

Enter number upto which Fibonacci series to print: 15   Fibonacci series upto 15 numbers : 1 1 2 3 5 8 13 21 34 55 89 144 233 377 610