Do we really know that? Or have we only seen the sequences from people searching for Numberwang? Has a number been both Numberwang (or Wangernumb) and not Numberwang (or Wangernumb)?
> A NumberWang "board game in a box" was produced in 2008, including the board, numbers, two 400-sided dice, special hosting accessories and all 37 volumes of the rules so that you can say "That's NumberWang!" with confidence. For everyone from ages 8 to 88.
So even the true fan may falter in his or her judgement.