Short J Group

Short J group  

The short J group is actually a tripod group followed by the - exchange. It is alive as it stands. A White stone around a makes it unsettled, however. Playing at b is a wrong and leaves the group unsettled.

It should not be confused with the J group.

Table of contents Alive The straight Short J group Short J group with extra leg An extra white stone on the upper side

Table of diagrams Short J group Attempt 1 Attempt 2 Attempt 3 Attempt 4 Attempt 4, alternative Mistake after follow-up 4 Straight Short J group [Short J group with extra leg] An extra White stone on the upper side continuation

Index of sub-pages Short J Group

Alive

Attempt 1  

If blocks, then lives. Black has (on average) 4 points of territory.

Attempt 2  

If makes an attachment here, then hanes. and are miai for life.

Attempt 3  

The descent at is answered by as well. Black has only 2 points of territory, the best result for White.

Attempt 4  

and is probably the strongest attack, threatening a ko. The throw-in at is neccessary for life. The result is oshitsubushi.

Attempt 4, alternative  

If captures, then and lives by oshitsubushi as well.

Mistake after follow-up 4  

here would be a mistake, because turns the whole group into a ko.

The straight Short J group

Straight Short J group  

If is as in this diagram (instead on a) as before than white can kill with the eye-stealing tesuji of , making a placement and aiming at setting up a snapback at b. Black is dead.

Short J group with extra leg

Short J group with extra leg  

While the short J group is alive black must be careful not to play the - exchange and then play tenuki the group now becomes unsettled see Short J group with extra leg for details

An extra white stone on the upper side

An extra White stone on the upper side  

Black must also be careful when White has played at if he does nothing While can kill him with White a. Black to play should defend at b.

(If White has a stone at b, Black needs to play a or d. If White has a stone at c, Black needs to play a. SeeAttempt 1 above.)

continuation  

After , and reduce the corner to one eye and although can be captured (Black a White b it is only a false eye.