Answers.Body: <p>Here's a unique 4 ply solution. 1. Na3 a6 2. g4 h5 hasn't every been played by anyone as far as I can tell... yet.</p>
  <p>Obviously as soon as someone answers this question, I could play a friend on lichess and &quot;knock out&quot; any answer. So the question really only makes sense when you discuss serious games between masters. In which case, already 1. Na3 a6 is a novelty in &quot;professional&quot; play.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2024-02-14T06:55:50.563Z
Answers.Text: Consider the question as being restricted to games that existed before the question was asked.
Answers.UserDisplayName: Steve Bennett
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2024-02-14T07:03:33.620Z
Answers.Text: `1. Na3 f6 2. h3 b5` seems to be another.
Answers.UserDisplayName: Steve Bennett
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2024-02-14T07:06:18.537Z
Answers.Text: And quite a few possibilities `1. d3 Nh6 2. Bd2 ??`
Answers.UserDisplayName: Steve Bennett
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2024-02-15T05:48:17.113Z
Answers.Text: Alekhine 2 Qg4/Qh5, or Scandinavian 2 Bc4/Qg4 ? . . .  (Or even 2 Ba6; likewise Caro-Kann 2 Bb5 and various sequences where White's second move hangs wB on a6 or h6)
Answers.UserDisplayName: Noam D. Elkies
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2024-02-14T05:16:47.197Z
Answers.LastActivityDate: 2024-02-14T05:16:47.197Z
Answers.UserDisplayName: NoseKnowsAll
Answers.Body: <p>There seem to be a few 4 ply lines that have 0 games on Lichess.</p>
  <ul>
  <li><code>1. Na3 f6 2. h3 b5</code></li>
  <li><code>1. Nh6 2. Bd2 ..</code></li>
  <li><code>1. f3 h6 2. Na3 f5</code></li>
  </ul>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2024-02-14T09:42:53.673Z
Answers.Text: Oh, hmm. I just realised I'm reading the stats wrong. The opening database Lichess gives are based on positions, not games, so they include transpositions. There are potentially more games that haven't been played, even if the positions they would reach have.
Answers.UserDisplayName: Steve Bennett
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2024-02-14T09:40:25.000Z
Answers.LastActivityDate: 2024-02-14T09:40:25.000Z
Answers.UserDisplayName: Steve Bennett
Body: <p>In the publicly available databases (at all levels of play, including Lichess), what is the shortest unique sequence of moves from the opening which has never occurred? (That is, if it were played, it would be a novelty.)</p>
  <p>Are there, for instance, any 2 move sequences?</p>
  
Tags: <opening><database>
Title: What is the shortest game that has never been played?
ThreadText: # What is the shortest game that has never been played?
  
  (Asked by: username_0 on 2024-02-13)
  
  In the publicly available databases (at all levels of play, including Lichess), what is the shortest unique sequence of moves from the opening which has never occurred? (That is, if it were played, it would be a novelty.)
  
  Are there, for instance, any 2 move sequences?
  
  **Tags:** opening, database
  
  
  ---
  
  ## 2 answers
  
  ### Answer by username_1 on 2024-02-14. Score: 4
  
  Here's a unique 4 ply solution. 1. Na3 a6 2. g4 h5 hasn't every been played by anyone as far as I can tell... yet.
  
  Obviously as soon as someone answers this question, I could play a friend on lichess and "knock out" any answer. So the question really only makes sense when you discuss serious games between masters. In which case, already 1. Na3 a6 is a novelty in "professional" play.
  
  > **Comments:**
  > **username_0**: Consider the question as being restricted to games that existed before the question was asked.  
  > **username_0**: `1. Na3 f6 2. h3 b5` seems to be another.  
  > **username_0**: And quite a few possibilities `1. d3 Nh6 2. Bd2 ??`  
  > **username_2**: Alekhine 2 Qg4/Qh5, or Scandinavian 2 Bc4/Qg4 ? . . .  (Or even 2 Ba6; likewise Caro-Kann 2 Bb5 and various sequences where White's second move hangs wB on a6 or h6)  
  
  ---
  
  ### Answer by username_0 on 2024-02-14. Score: 0
  
  There seem to be a few 4 ply lines that have 0 games on Lichess.
  
  * `1. Na3 f6 2. h3 b5`
  * `1. Nh6 2. Bd2 ..`
  * `1. f3 h6 2. Na3 f5`
  
  > **Comments:**
  > **username_0**: Oh, hmm. I just realised I'm reading the stats wrong. The opening database Lichess gives are based on positions, not games, so they include transpositions. There are potentially more games that haven't been played, even if the positions they would reach have.  
  
  ---
  
  