Meanwhile, for the game of Go, as played on a standard 19x19 board, we have:
The maximum number of possible next moves is 361, which happens only in the initial empty position.
The 361 hardest-to-reach positions (assuming logical rules like [2]) are all the positions with 360 white stones and 1 empty point. these take 2*361 = 722 ply to reach, with black passing all their turns.
And these answers were found without checking all 208168199381979984699478633344862770286522453884530548425639456820927419612738015378525648451698519643907259916015628128546089888314427129715319317557736620397247064840935 legal positions :-) [1]
A game of Go can be legally infinite due to recaptures. (player passes 360 times, then eats the entire board and it starts over).
It's also a natural infinite game due to Kos which can be the best move to play. This requires a set of extra rules to prevent. (Ko, superKo, triple kos, etc)
White cannot play on the last empty point as this would be suicide, which is prevented by the (assumed) superko rule forbidding repetition of the empty position.
The maximum number of possible next moves is 361, which happens only in the initial empty position.
The 361 hardest-to-reach positions (assuming logical rules like [2]) are all the positions with 360 white stones and 1 empty point. these take 2*361 = 722 ply to reach, with black passing all their turns.
And these answers were found without checking all 208168199381979984699478633344862770286522453884530548425639456820927419612738015378525648451698519643907259916015628128546089888314427129715319317557736620397247064840935 legal positions :-) [1]
[1] https://tromp.github.io/go/legal.html
[2] https://tromp.github.io/go.html