# [05AB1E], 5 [bytes] ∞å0k> [Try it online!][TIO-lelfds6u] [05AB1E]: https://github.com/Adriandmen/05AB1E [TIO-lelfds6u]: https://tio.run/##yy9OTMpM/f//Uce8w0sNsu3@/4821FEw0lEwjgUA "05AB1E – Try It Online" [bytes]: https://github.com/Adriandmen/05AB1E/wiki/Codepage #### Explanation ```python ∞å0k> # Implicit input ∞ # For each number in the infinite list [1, 2, 3, ...] å # Is it in the input? 0k # Get the index of the first 0 (0-indexed) > # And increment it to make it 1-indexed ```