Get Maximum in Generated Array LeetCode solution in JavaScript

1
var getMaximumGenerated = function (n) {
2
  if (n === 0) return 0;
3
  if (n === 1) return 1;
4
  let arr = [0, 1];
5
  let max = 0;
6
  for (let i = 0; i < n; i++) {
7
    if (2 <= 2 * i && 2 * i <= n) {
8
      arr[2 * i] = arr[i];
9
      if (arr[i] > max) max = arr[i];
10
    }
11
    if (2 <= 2 * i && 2 * i + 1 <= n) {
12
      arr[2 * i + 1] = arr[i] + arr[i + 1];
13
      if (arr[i] + arr[i + 1] > max) max = arr[i] + arr[i + 1];
14
    }
15
  }
16
  return max;
17
};