# Tribonacci series in JavaScript

JavascriptWeb DevelopmentFront End Technology

## Tribonacci Series:

The tribonacci sequence is a generalization of the Fibonacci sequence where each term is the sum of the three preceding terms.

For example, the first few terms of the tribonacci series are −

0,1,1,2,4,7,13,24,44,81,149

We are required to write a JavaScript function that takes in a number, say num, as the only argument.

The function should then return an array of num elements, containing the first num terms of the tribonacci series.

## For example:

f(6) = 0,

## Example

Following is the code:

const tribonacci = (num = 1) => {
if (num === 0 || num === 1 || num === 2){
return 0;
};
if (num == 3){
return 1;
}else{
return tribonacci(num - 1) +
tribonacci(num - 2) +
tribonacci(num - 3);
}
}
const trib = num => {
const res = [];
for (let i = 1; i <= num; i++){
res.push(tribonacci(i));
};
return res
};
console.log(trib(15));

## Output

Following is the console output −

[ 2, 1, 4, 3, 6, 5 ]
Updated on 18-Jan-2021 04:40:12