The shape created by the two White stones is called hazama tobi in Japanese. Usually it is a bad shape, as it can easily be cut apart. At special circumstances, though, it can be very powerful, but you should have an answer ready if your opponent plays in the middle (the marked point).
It is also called an elephant's move, because the elephant in Chinese chess moves this way. (In Chinese: 象飞 (elephant's jump) or 象步 (elephant's step) and 象眼 - the elephant's eye for the marked place.)
In joseki, there are two main uses from the 3-4 point.
This pincer isn't often played now, so is rarely seen. Popular enough in the first half of the twentieth century.
This furikawari idea is a typical sequel.
This is still current as joseki.
This leads to a large-scale sacrifice variation known as the Kajiwara joseki. White [1] gives up around 20 points in the corner for the sake of imperfect outside influence. Not an easy line in practice. It is still being played by the pros.
BramGo: This variation I saw recently in the 6th Round of the 29th Meijin title. I am not sure if it is something new, but personally, I had never seen it before. After w8 black tenukied, to approuch the corner at the topright of this diagram. White ignored this and played A.
White can also play this way for the corresponding 4-4 pincer.
White probably played that way to gain influence; so Black 1 and so on are natural, starting a pushing battle in the centre. Black has to be careful not to create difficulties for the corner 4-4 stone, though. It isn't easy to say when Black can or should stop pushing.
Frs: Does a Japanese, English or animal Go term exist for Black's shape or/and ?
Sebastian: How about "Mammoth"? For Chinese, I'd propose "猛傌", pronounced "mengma". (This would mean mammoth, if the second character were "獁". By replacing it with the old character for "knight in chess" - which is pronounced the same way - it now reads "fierce knight".)
It's tough to call Black connected, there, so the shape is somewhat nameless like many others... The potential use for such a shape depends so much on the surrounding area. Coconuts
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[1] Robert Pauli: Seems, Black and not White is trading corner for influence, not? I searched for "Kajiwara joseki" (with double quotes) and nothing was found??
Charles Try 3-4 point low approach two-space high pincer hazama tobi.
Robert Pauli: Ah, I see. Thanks.
I've also seen this one played a few times jumping to the 2nd line as a tesuji... I'll try to find an example... (Wrote it here hoping somebody else would do it.. ;p) Reuven
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