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KGS 5d


Table of contents Table of diagrams
Spiral-3 opening and spiral-n openings for n=1,2,4,5,6,7,8,9 labeled by corresponding alphabets
Spiral-9 opening
Spiral-7 opening
Spiral-6 opening
Spiral-5 opening
Cyclic daidaigeima opening
How not to use spiral-n
Generalized Chinese opening

I maintain the rank histogram pages.

Selected Games

Against Professionals

This game was played against Jin Jing 2p using another account. I took 4 stones. I believe this is my second victory against professionals -- the first time was an 8-stone game many years ago.

[ext] smartrobot-NobiNobita

Against Computers

I play a lot against computers on KGS. They are unorthodox but creative and very sensitive to the global balance.

Here are two even games played against Zen19S 5d in 2013. (Zen defeated Takemiya Masaki 9p in a 4-stone handicapped game in 2012.)

  • [ext] rsun-Zen19S: Zen likes to start with hoshi and often makes the sanrensei formation. Given its preference for moyo and the significant komi (7.5), it is natural for White to adopt a territorial strategy in the beginning. As it is usually the case, the question is how to reduce its moyo effectively.
  • [ext] Zen19S-rsun: In this game I decided to use Zen's favorite opening, the sanrensei. Zen made a terrible mistake in handling my corner invasion and could never turn the tables.

I managed to beat Many Faces 3d giving 6 stones.

Opening Studies

As the title misleads, these are not studies at all. Just for fun.

Spiral-n Opening

[Diagram]

Spiral-3 opening and spiral-n openings for n=1,2,4,5,6,7,8,9 labeled by corresponding alphabets

Inspired by the Shusaku fuseki, I have invented the spiral-n opening, where n is the smallest number of the coordinates of the black stones. Hence the opening moves of the Shusaku fuseki can be classified as (an incomplete) spiral-3.



However, such an opening will almost never come to completion, as white will almost always play at an empty corner. For the same reason, spiral-4 (d) will also never be realized. It is obvious that spiral-1 and spiral-2 are bad and should be rejected outright. Note that spiral-9 (i) forms a cyclic kosumi (i.e., an eye) and spiral-8 (h) is a cyclic ogeima.

[Diagram]

Spiral-9 opening

The spiral-9 opening may be discussed in beginner go books. As the saying goes, a ponnuki at tengen is worth 30 points. However, as White gets four corners without sacrificing a stone, this opening is too inefficient for Black. Likewise, spiral-8 may be inefficient as well.



Applying Rolle's Theorem to Spiral-n

Observe the trend as n increases. For n=1,2, the openings are bad. For n=3,4, the openings become acceptable, but completing it becomes bad, as Black blindly attaches into White's corners. For n=8,9, the openings become inefficient. If you believe, as I do, that the strength of the spiral-n opening increases for low n and decreases for high n, then by (improper use of) [ext] Rolle's Theorem, there must exist an optimum n where the spiral-n opening is the strongest.

Unfortunately, this optimum n cannot be found analytically. Based on intuition, it seems to me that the spiral-6,7 openings should be the best.

[Diagram]

Spiral-7 opening

The spiral-7 opening radiates strong influence toward the entire board.

[Diagram]

Spiral-6 opening

Compared to spiral-7, the spiral-6 opening puts more pressure on White's corners.

[Diagram]

Spiral-5 opening

The spiral-5 opening has 4 unusual kakaris. However, it is very likely that White will respond locally and Black may not be able to complete the formation.


Cyclic Daidaigeima Opening

[Diagram]

Cyclic daidaigeima opening

The cyclic daidaigeima opening, as the name suggests, contains 4 daidageimas, forming a relatively solid shape. However, it cannot be classified as a spiral-n opening. It is clear that a spiral-n opening is composed of 2*(9-n)-space extensions. Thus, odd-space extensions cannot be spiral-n.

It may still be too slow.



Strategies

Although spiral-n has a 4-fold rotational symmetry about tengen, mirror symmetry is spontaneously broken. Hence, Black's 5th move is greatly influenced by the symmetry of White's first 4 moves.

[Diagram]

How not to use spiral-n

One must never use the spiral-n opening to defend the tengen territory. That completely misses the point. Instead, one should overplay reasonably (an oxymoron?) at sides and corners to provoke fights, so that the first 4 moves can become effective.



Of course, there is always the possibility that black cannot complete the formation due to an existing white stone. However, Black should not feel that s/he is at a disadvantage.

Generalized Chinese Opening

[Diagram]

Generalized Chinese opening

Vertical and diagonal Chinese opening. Other possibilities marked b-g. Note that Go Seigen once played 3-3, 4-4, 10-10, whereas the diagonal Chinese fuseki is 3-3, 4-4, 9-9.


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