Renju

Renju (Japanese: 連珠) is the professional variant of Gomoku. It was named Renju by Japanese journalist Ruikou Kuroiwa (黒岩涙香) on December 6, 1899 in a Japanese newspaper Yorozu chouhou (萬朝報). The game is played with black and white stones on a 15×15 gridded Go board.

Renju eliminates the "Perfect Win" situation in Gomoku by adding special conditions for the first player (Black).

Rules

Opening rules

Unlike Gomoku, Renju has a unique sequence of opening moves called an "opening rule". There are several certified opening rules. The list of requirements for new opening rules as approved by the RIF General Assembly in 2003 was:

I. Traditions

• The basic Renju rules must be kept.
• The opening stage must not exceed 5 moves.
• All 26 canonical openings must be possible and only 26 canonical openings can be possible.
• All present realistic variants must be possible.
• The moves located very closely near the edges of a board during the opening stage are not preferable.

II. Simplicity and attraction

• New rules must be simple to study.
• New rules must be simple to play for beginners. The situation when in significant part of cases a beginner will have the lost position already after the first 5 moves is not good.
• The rules must be systematic and attractive.

III. Creativity

• The number of possible creative variants must be significantly greater than now. These variants must be achieved under the optimal strategy of both players.
• The chances of sides to win must be practically equal.
• The situation when during the opening stage the player who make a move does not interested in the forming of equal and creative position is not preferable. (Example: indirect 2nd move in previous opening rules).
• The rules must give the chance for both players to avoid the position after the opening stage well known for the opponent.
• The knowledge of theory and deep own analyses must give an advantage but the player with a good imagination must have chances against this.

An example of such opening rule (namely "RIF opening rule") follows.

1. The first player places 2 black stones and 1 white stone on the board thus forming opening pattern.
2. The second player now chooses whether to play black or white.
3. White then places one more stone on the board.
4. Black places 2 stones on the board.
5. White removes one of the two black stones from the previous move.
6. White places a white stone.

After this sequence is complete, Black and White continue to take turns to place their stones.

The Extra General Assembly of Renju International Federation in 2008 created three new sets of rules for openings that are to replace the above old sequence of moves:^[1] Soosõrv, Taraguchi, and Yamaguchi. Also a rejection system for their use was approved. The General Assembly of Renju International Federation in 2009 certified Sakata opening rule as proposed by Russia. The General Assembly of Renju International Federation in 2011 certified modified opening rules such as Taraguchi-N and Soosõrv-N.

Disallowed moves

There are certain moves that Black is not allowed to make:

• Double three – Black cannot place a stone that builds two separate lines with three black stones in unbroken rows (i.e. rows not blocked by white stones).
• Double four – Black cannot place a stone that builds two separate lines with four black stones in a row.
• Overline – six or more black stones in a row.

Winning

Black can win the game only by placing five black stones in a row (vertically, horizontally or diagonally).

White can win by either:

• getting five (or more) white stones in a row
• forcing Black to make a forbidden move (see above).

World championships

World Championships in Renju have occurred every second year, since 1989. Since 2009 the opening rule being played is Yamaguchi.

Previous World Championships have taken place in the following places:

Title year	Hosting city, country	Champion	Opening rule
1989	Kyoto  Japan	Shigeru Nakamura	Swap opening rule
1991	Moscow  Soviet Union	Shigeru Nakamura	Swap opening rule
1993	Arjeplog  Sweden	Ando Meritee	Swap opening rule
1995	Tallinn  Estonia	Norihiko Kawamura	Swap opening rule
1997	Saint Petersburg  Russia	Kazuto Hasegawa	RIF opening rule
1999	Beijing  China	Ando Meritee	RIF opening rule
2001	Kyoto  Japan	Ando Meritee	RIF opening rule
2003	Vadstena  Sweden	Tunnet Taimla	RIF opening rule
2005	Tallinn  Estonia	Ando Meritee	RIF opening rule
2007	Tyumen  Russia	Wu Di	RIF opening rule
2009	Pardubice  Czech Republic	Vladimir Sushkov	Yamaguchi opening rule
2011	Huskvarna  Sweden	Cao Dong	Yamaguchi opening rule
2013	Tallinn  Estonia	Tunnet Taimla	Yamaguchi opening rule
2015	Suzdal  Russia	Qi Guan	Yamaguchi opening rule

Team World championships

Team World Championships in Renju have occurred every second year, since 1996. Since 2010 the opening rule being played is Yamaguchi. The results are following.

Title year	Hosting city, country	Champion team
1996	Saint-Petersburg  Russia	Russia (Ilyin D., Peskov S., Sinyov I., Nikonov K., Kozhin M.)
1998	Yerevan  Armenia	Sweden (Karlsson S., Jonsson P., Asplund B., Andersson T.)
2000	Tallinn  Estonia	Russia (Sinyov I., Klimashin A., Sushkov V., Salnikov P., Kozhin M.)
2002	Vadstena  Sweden	Russia (Salnikov P., Klimashin A., Artemyev S., Skouridin A., Semyonov V.)
2004	Tyumen  Russia	Russia (Sushkov V., Klimashin A., Chingin K., Nikonov K., Sinyov I.)
2006	Tallinn  Estonia	Russia (Sushkov V., Chingin K., Artemyev S., Savrasova Yu., Vershinin P.)
2008	Helsinki  Finland	Estonia (Taimla T., Oll A., Purk A., Soosorv A., Lents J.)
2010	Tokyo  Japan	China (Li Yi, Cao Dong, Yin Licheng, Xi Zhenyang)
2012	Beijing  China	Japan (Yuuki Oosumi, Shigeru Nakamura, Takahiro Kudomi, Kazumasa Tamura, Hiroshi Okabe, Tomoharu Nakayama)
2014	Taipei  Taiwan	Estonia (Taimla T., Hobemagi M., Soosorv A., Lents J., Meritee A.)
2016	Tallinn  Estonia	Estonia (Oll A., Taimla T., Hobemagi M., Pajuste R., Lents J.)

Renju World Championships via Correspondence

World Championships in Renju via Correspondence were held in 1982 to 1993 (by paper letters, later by e-mails) and now are played every year since 1996 with an exception in 2009, 2010. Since 2014 the opening rule being played is Soosõrv-7. The results follow.

Title year	Champion	Country
1982	Sapronov, Vladimir	Soviet Union
1984	Nosovsky, Alexander	Soviet Union
1985	Nosovsky, Alexander	Soviet Union
1991	Poghosyan, Albert	Soviet Union
1993	Poghosyan, Albert	Armenia
1996	Reims, Aldis	Latvia
1997	Tarannikov, Yuri	Russia
1998	Fedorkin, Oleg	Russia
1999	Fedorkin, Oleg	Russia
2000	Reims, Aldis	Latvia
2001	Nikonov, Konstantin	Russia
2002	Lunkin, Vitaly	Russia
2003	Chen Wei	China
2004	Sun Chengmin	China
2005	Barykin, Victor	Russia
2006	No gold awarded
2007	Epifanov, Dmitry	Russia
2008	Zhang Jinyu	China
2011	Balanova, Jelena	Latvia
2012	Potapov, Alexey	Russia
2013	Sushkov, Vladimir	Russia
2014	Sushkov, Vladimir	Russia
2015	Nikonov, Konstantin	Russia

Members of the Renju International Federation

The Renju International Federation was founded by 3 founder members in August 8, 1988 in Stockholm, Sweden. Up to 2016, there have been 20 members in the Renju International Federation, among which 15 members are active. The list of members follows.^[2]

Member	Year of joining	Status
Japan	1988	Founder Member
Russia	1988	Founder Member[lower-alpha 1]
Sweden	1988	Founder Member
Canada	2003	Member
China	1996	Member
Macau, China	2015	Member
Chinese Taipei	1999	Member
Czech Republic	Before 2003	Member
Estonia	Before 1995	Member
Finland	Before 2006	Member
Greece	2016	Member
South Korea	2001	Member
Poland	2009	Member
Turkey	2015	Member
Uzbekistan	1999	Member
Armenia	Before 1995	Idle
Azerbaijan	Before 1995	Idle
Belarus	Before 1995	Idle
Latvia	Before 1995	Idle
Ukraine	Before 1995	Idle

See also

• Game complexity
• Connect6
• Gomoku
• Go (board game)
• Irensei

Notes

References

• Renju International Federation
• SOLVING RENJU by János Wágner and István Virág, ICGA Journal, 2001

Further reading

• Five-in-a-Row (Renju) For Beginners to Advanced Players ISBN 4-87187-301-3

External links

• Renju International Federation has complete rules and history of the game
• Renju at BoardGameGeek