American Go E-Journal » 2015 » April

by John Power, Japan Correspondent for the E-Journal

Takao evens score in Judan: The fourth game of the 53rd Judan title match was played at the Nihon Ki-in in Tokyo on April 15. Playing black, Takao Shinji Judan forced a resignation after 167 moves and drew level with the challenger, Ida Atsushi 8P. Ida made a dubious move in the opening (move 46), creating a weak group and letting Takao take the lead. He kept up the pressure and shut Ida out of the game. The deciding game will be played at the same venue on April 22.

Meijin League: One game was played in the 40th Meijin League on April 16. Yamashita Keigo 9P (B) beat Kanazawa Makoto 7P by 10.5 points. Yamashita improved his score to 3-1, just behind Ko Iso 8P on 4-1. On 1-4, Kanazawa is in bottom place and his chances of keeping his seat don’t look good.

More details on quadruple ko: This week’s Go Weekly printed an interview with Kono Rin about his quadruple ko the previous week (see my last report). Some interesting points came up. First of all, Go Weekly states that a quadruple ko comes up once every eight thousand games. Despite this, Kono has featured in two of the 11 recorded cases in Japan and also in a case of triple ko, a record matched only by Cho Chikun (three triple kos). According to Kono, he deliberately set up these kos as the only way to avoid losing the games concerned. In his game against Mitani Tetsuya, Kono set up the second of the double kos in an attempt to make Mitani add a reinforcement; compared to the regular endgame sequence, that would have cost Mitani two thirds of a point. Both Kono and Mitani thought that they were fighting over whether Mitani (black) ended up seven or six points ahead on the board (komi is six and a half). That’s why neither gave way and they agreed to make the game a “no result.” It became clear later, however, that both players had been miscounting the score by one point. Mitani could have given way, as he would still have won the game by half a point. That shows how important counting is. (By the way, Mitani lost the replay on the 13th.) Kono also realized that he (and probably many other professionals) didn’t have an accurate knowledge of the rules. When the quadruple ko started, the players had someone call the referee (probably only one referee was on duty for all the games being played that day). They thought that the referee had to make the decision to declare the game a no-result, but Article 12 of the Japanese rules states: “When the same whole-board decision is repeated during a game, if the players agree, the game ends without result.” In other words, the referee’s job is to oversee the process and confirm the agreement. Kono also commented that he mistakenly thought that the game automatically became a no-result if the same whole-board position was repeated, but the only reference to whole-board repetition is the rule quoted above. He said that he and Mitani could have kept capturing and recapturing the kos all night without infringing the rules. The rule just gives the players the option of agreeing to a no-result to avoid this futility. The reporter interviewing Kono, Sekine Shingo, surmises that go players have perhaps got the go rule mixed up with the shogi rule. In shogi, the rule apparently is that a game is replayed if the same whole-board position occurs four times. The Japanese rules are only one and a half pages long (though there’s a longer commentary), so it’s surprising that players are not completely familiar with them. One reason may be that the average professional would have to play for a dozen lifetimes to experience a no-result.

by John Power, Japan Correspondent for the E-Journal

Ida takes lead in Judan: The second game of the 53rd Judan title match was held at the Kuroyon Royal Hotel in the city of Omachi in Nagano Prefecture on April 9. Omachi has become closely linked with the Judan tournament: this is the 22nd year in a row that a game from the title match game has been staged here. Omachi is a gateway to the Northern Alps and it has sought to establish itself as “the Alps go village.” Four years ago, Ida Atsushi was the game recorder for the Judan game held here and now he was playing in the title match, challenging Takao Shinji (right). 
        The game started with fierce fighting, and the first notable move was a move by Ida, playing black, that defied a go proverb by letting the opponent drive a wedge through some neighbouring stones (the proverb is, “don’t let yourself be split into two”). Despite this, Ida got off to a reasonable start. In the middle-game fighting, Ida took a small lead and managed to hold on to it to the end. He won by 2.5 points after 277 moves. After making a bad start in the title match, he has won two games in a row and now needs just one more win to  take the title.

Ko Iso leads Meijin League: Two games were played in the 40th Meijin League last week. On April 6, Ko Iso 8P (B) beat Murakawa Daisuke by 3.5 points. On April 9, So Yokoku 9P (B) Cho U 9P by half a point. There are four players with only one loss in the league, but Ko holds the provisional lead by virtue of having completed five rounds. His score is 4-1; the other players are Rin Kono 9P on 3-1 and Yamashita Keigo 9P and Takao Shinji 9P, both on 2-1.

Quadruple ko: A game between Kono Rin 9P (left) and Mitani Tetsuya 7P (black) played in the main section of the Gosei tournament on April 6 was declared no-contest (by agreement between the players) because of a quadruple ko. There were two double kos in Black’s position, one in the top right, the other in the bottom left. So long as these kos continued, the game could not end, but it was so close that Black could not afford to add a stone inside his territory to finish off either ko.
        This was the 24th no-contest in an official tournament at the Nihon Ki-in. Eleven of them were from quadruple kos, ten from triple kos, and one from a quintuple ko. The other two were from “chosei” or “eternal (or long) life” (an example is given on page 185 of The Go Players Almanac). Chosei is a hypothetical position that first occurred in a professional game in 1993 and then again in 2009. According to Wikipedia, it also appeared in a Korean game in 2013. Incidentally,  a chosei is embedded in the floor of the concourse of Ichigaya Station (the closest station to the Nihon Ki-in), just before the ticket gates.

LG Challengers Cup: To commemorate the 20th anniversary of the LG Cup, an international tournament for players 18 and under was held at the Korean Kiwon (Ki-in) in Seoul on April 10 and 11. At stake was a seat in the main LG tournament, which starts on June 8. There were eight players from Korea, including inseis, and four each from Japan and China. Representing Japan were Ichiriki Ryo 7P, Kyo Kagen 3P, Fujisawa Rina 2P, and Mutsuura Yuta 1P. Three of these players were eliminated in the first round, but Kyo Kagen made it to the second day; he lost to the eventual winner of the tournament, Byan Sang-il 3P of Korea, in the semifinals.