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# Gaurav Patil Blog

Follow # Find the Fibonacci Series up to Nth Term in Javascript Language

## We will discuss three methods to solve this problem using Javascript

Gaurav Patil
·Feb 20, 2023·

• Method 1: Using Iteration
• Method 2: Using Recursion
• Method 3: Using Formula
• Conclusion

Hi everyone today we Find the Fibonacci Series up to Nth Term in Javascript Language. let's discuss how to solve this problem statement. if you want to check out yesterday's problem click here.

Given an integer input for the Nth value, the objective is to Find the Fibonacci Series up to the Nth term using Loops and recursion in Javascript Language. To do so we’ll use the following methods,

• Method 1: Using Iteration

• Method 2: Using Recursion

• Method 3: Using Formula

## Method 1: Using Iteration

### Algorithm

• step 1: Initialize the value of `num` to 15.

• step 2: Initialize variables `a` and `b` to 0 and 1 respectively.

• step 3: Print the values of `a` and `b` separated by a comma and a space using `console.log()`.

• step 4: Initialize a variable `nextTerm`.

• step 5: For each value of `i` from 2 to `num` (exclusive):

1. Calculate the value of `nextTerm` as the sum of `a` and `b`.

2. Assign the value of `b` to `a`.

3. Assign the value of `nextTerm` to `b`.

4. Print the value of `nextTerm` followed by a comma and a space using `console.log()`.

• step 6: End the loop.

### Javascript Code

``````let num = 15;
let a = 0, b = 1;

// Here we are printing 0th and 1st terms
console.log(a + " , " + b + " , ");

let nextTerm;

// printing the rest of the terms here
for (let i = 2; i < num; i++) {
nextTerm = a + b;
a = b;
b = nextTerm;
console.log(nextTerm + " , ");
}
``````

### Output

0 , 1 , 1 , 2 , 3 , 5 , 8 , 13 , 21 , 34 , 55 , 89 , 144 , 233 , 377

## Method 2: Using Recursion

### Algorithm

• step 1: Initialize variables `a` and `b` to 0 and 1 respectively.

• step 2: Initialize a variable `nextTerm`.

• step 3: Define a function `fib` that takes an integer `n` as input.

• step 4: If `n` is greater than 0, do the following:

1. Calculate the value of `nextTerm` as the sum of `a` and `b`.

2. Assign the value of `b` to `a`.

3. Assign the value of `nextTerm` to `b`.

4. Print the value of `nextTerm` followed by a comma and a space using `console.log()`.

5. Recursively call the `fib` function with `n - 1` as the input.

• step 5: End the if statement.

• step 6: Return 0.

• step 7: Initialize the value of `n` to 15.

• step 8: Print the values of `a` and `b` separated by a comma and a space using `console.log()`.

• step 9: Call the `fib` function with `n - 2` as the input.

### Javascript Code

``````let a = 0, b = 1, nextTerm;

function fib(n) {
if (n > 0) {
nextTerm = a + b;
a = b;
b = nextTerm;

console.log(nextTerm + " , ");
fib(n - 1);
}
return 0;
}

let n = 15;
// Here we are printing 0th and 1st terms
console.log(a + " , " + b + " , ");

// n-2 as 2 terms already printed
fib(n - 2);
``````

### Output

0 , 1 , 1 , 2 , 3 , 5 , 8 , 13 , 21 , 34 , 55 , 89 , 144 , 233 , 377

## Method 3: Using Formula

### Algorithm

• step 1: Initialize variables `a` to 0 and `b` to 1.

• step 2: Define a function `fib` that takes a parameter `n`.

• step 3: Inside the `fib` function, create an array `f` of length `n+1`.

• step 4: Set the first two elements of the array `f` to 0 and `f` to 1.

• step 5: Print the values of the first two elements of the array.

• step 6: Using a loop, compute and store the fibonacci sequence in the array `f` for values of `i` from 2 to `n-1`.

• step 7: For each value of `i`, compute the sum of the previous two elements of the array `f` and store the result in `f[i]`.

• step 8: Print each value of the array `f` computed in the previous step.

### Javascript Code

``````let a = 0, b = 1, nextTerm;

function fib(n) {
let f = new Array(n + 1);

f = 0;
f = 1;

console.log(f + " , " + f + " , ");

for (let i = 2; i < n; i++) {
f[i] = f[i - 1] + f[i - 2];
console.log(f[i] + " , ");
}
}

let n = 15;
fib(n);
``````

### Output

0 , 1 , 1 , 2 , 3 , 5 , 8 , 13 , 21 , 34 , 55 , 89 , 144 , 233 , 377