Taraguchi opening rule

Taraguchi opening rule is a renju opening rule. It was proposed by Yusui Yamaguchi as an advancement of a Tarannikov opening rule and therefore it was named with a combination of these two names. It has an enhancement, Taraguchi-N opening rule.

The choice 1 (after the 4th move):

The choice 2 (after the 4th move):

This rule offers a good variety of playable variants in the openings that aren't playable by Yamaguchi opening rule like 13D, 13I, 12D, 10D.

On the other hand, this rule limits playable openings to those that don't have five winning fifth moves, so 2D, 2I and some other openings become unavailable. The Taraguchi-N opening rule solves this problem.

This opening rule is official opening rule for Renju World Championship via Correspondence being held in 2012, European Championships since 2010 and some minor international tournaments.

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