Check out example codes for "recursive function for fibonacci series in java javascript". It will help you in understanding the concepts better.

Code Example 1

var fib = function(n) {
  if (n === 1) {
    return [0, 1];
  } else {
    var arr = fib(n - 1);
    arr.push(arr[arr.length - 1] + arr[arr.length - 2]);
    return arr;
  }
};

console.log(fib(8));

Code Example 2

var fib = function(n) {
  if (n === 1) {
    return [0, 1];
  } else {
    var arr = fib(n - 1);
    arr.push(arr[arr.length - 1] + arr[arr.length - 2]);
    return arr;
  }
};

console.log(fib(2));

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