According to the America’s Foundation for Chess, that is the number of ways to play the first 10 moves. I'm assuming ten moves per side, ten black, ten white.

Wow, that is tiny!

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Patience, grasshopper.

Forgot to link where I found it (paragraph 20) http://www.chess-poster.com/english/not ... u_know.htm

Also found at:

https://www.chess.com/forum/view/genera ... sibilities

https://www.reddit.com/r/todayilearned/ ... 0000_ways/

The 20th root of that number is approximately 29. So that says there are, on average, 29 possible moves in each position for the first 20 moves of the game. That sounds reasonable.

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Still officially AGA 5d but I play so irregularly these days that I am probably only 3d or 4d over the board (but hopefully still 5d in terms of knowledge, theory and the ability to contribute).