Print Fibonacci series using recursive function

fibonacci.js

function fib(num) {

    let sequence = [0, 1]

    function helper(sequence, num) {
        const length = sequence.length

        // get sum of last two numbers
        let sum = sequence[length - 1] + sequence[length - 2]

        if (sequence.length > num) {
            return sequence
        }

        sequence.push(sum)
        helper(sequence, num)

        return sequence
    }

    helper(sequence, num)

    return sequence
}


fib(10)