Yamaguchi opening rule
This article includes a list of references, but its sources remain unclear because it has insufficient inline citations. (December 2016) (Learn how and when to remove this template message)
The sequence of moves implied by the rule follows.
- The first player (tentative black) puts one of the 26 openings and declares how many 5th moves will be offered in that game.
- The next player (tentative white) has a right to swap.
- The white player puts the 4th move anywhere on the board.
- The black player puts as many 5th moves on the board as it was declared before (symmetrical moves not allowed).
- The white player chooses one 5th from these offerings and plays the 6th move.
This rule is very close to an old RIF opening rule and therefore favorited. It gives an average variety of new playable variants in a good number of openings, but some of them (13ths and some others) don't become playable. More, this opening rule doesn't protect players from a 11D-draw variants.
Tournaments played by this rule
- http://renju.net/media/showrule.php?rule=5 Renju International Federation - description of Yamaguchi rule.
- http://renju.net/organizations/ga2008.php - RIF GA with rule description
- http://www.renjusha.net/8twc_info.html - Team World Championship-2010 organizer's site, Yamaguchi rule mentioned as tournament rule.
- http://renju.net/media/tourninfo.php?tournament_id=545 - Information about World Championship-2009 finals.
- Aivo Oll, My Opinion about the Current State of Opening Rules, Renju World 70-71.
- Kozhin M., Notes on the new opening rules, Renju World 68-69.