Weekly Go problems: Week 137

Here are the weekly Go problems for week 137.

Black plays first in all problems and all solutions are labeled ‘correct’. Have fun!

Easy Go problem

Sacrificing stones can be powerful tactic in a capturing race.

 

Download SGF File (Go Game Record)

 


Download the solutions to the easy problem as an SGF or PDF file.

 

Intermediate Go problem

This looks like a bit like joseki, but White is refusing to compromise…

 

Download SGF File (Go Game Record)

 


Download the solutions to the intermediate problem as an SGF or PDF file.

 

Hard Go problem

We’re continuing with the theme of this week’s easy problem, but you’ll need some sharper tesuji this time.

 

Download SGF File (Go Game Record)

 


Download the solutions to the hard problem as an SGF or PDF file.

 

Still want more Go problems?

You can find Go books packed full of life and death problems, tesuji problems and other valuable Go knowledge at the Go Game Shop.

Discuss other possible moves

If you have any questions or want to discuss any of these problems, please leave a comment below at any time. You can use the coordinates on the problem images to discuss a move or sequence of moves.

You can also download the solutions as a PDF or SGF file by clicking the links below each problem.

About David Ormerod

David is a Go enthusiast who’s played the game for more than a decade. He likes learning, teaching, playing and writing about the game Go. He's taught thousands of people to play Go, both online and in person at schools, public Go demonstrations and Go clubs. David is a 5 dan amateur Go player who competed in the World Amateur Go Championships prior to starting Go Game Guru. He's also the editor of Go Game Guru.

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Comments

  1. As usual, the third problem is magnificent: to me all the moves I intuitively thought wouldn’t work were correct. Keep them coming!

    Kind regards,
    Paul

    • David Ormerod says:

      Thanks Paul, Black’s third move in the main solution makes me smile. It’s that sort of satisfying tesuji that keeps me playing Go 🙂

  2. I like the 3rd problem. I have seen the theme after a couple of moves before, but I didn’t recognize it from the starting position.

    • David Ormerod says:

      It’s an interesting scenario Mark, and the move order is a bit unusual. Glad to hear you enjoyed it.

  3. I would love to see a few continuations of the main line of the intermediate problem after White extends to C2 – I don’t think they are all obvious.

    • David Ormerod says:

      That’s an interesting question. It’s sometimes difficult to know when to stop a problem, because we really like Go and don’t want to blast readers with too much information 🙂

      Here are some more variations for you to consider. Basically, it’s good enough for Black to capture White’s four stones and Black can also fight in the corner.

      Even though White can make a desperate ko, simply winning the ko (ignoring any ko threat) should be good enough for Black in most cases and the damage to White will be large (which diminishes the value of any ko threat White cares to make):

       

       

      • David Ormerod says:

        And I’ll have to fix the double escaping of HTML entities (the weird looking ’ stuff that appears in the comments) when I have more time.

        That happens because of a security feature in the code which is a bit over-zealous.

  4. Hello, David.

    Thanks for these problems, they are very good; especially the intermediate for me…I have a lot of these kind of situations in my games…

  5. Hi David.

    Thanks for your problems, Its always nice to have a new batch.
    I did enjoy the hard one, though of course I had to retry
    after a few initial failures.

    I have a question about the intermediate one though. In the diagram above you analyzed what happens if white extends at C2. However I feel W at C7 instead is better and more irksome for B. How should B respond to W C7 ? Should he fight at H4 or just capture at C2 ?

    • David Ormerod says:

      Hi Gil,

      Sorry for the slow reply. We’ve had some problems with the internet connection lately, which as you can imagine is quite inconvenient as far as GGG is concerned.

      I showed a possible ko at F1 in the comment above, but in practice it would be very difficult for White to fight that ko in most games.

      So the answer, as usual with Go, is ‘it depends’. Most of the time, Black could just fight at H4 without thinking about it (especially since H4 temporarily prevents the ko variation from being possible).

      This kind of ko is ‘heavy’ for White, because she risks so much by starting it. Another way of saying it is that White will lose so much when she loses the ko that it will be hard to find a big enough ko threat to make the trade worthwhile.

      Have a look at this diagram:

       

       

      So if White has plenty of huge ko threats, Black might decide to capture at C2. But under normal circumstances that’s not necessary and Black can come back to defend in the corner much later in the game.

  6. Liked the hard one. Though I cannot say why without giving the game away a bit… 🙁

    • David Ormerod says:

      Yes, it’s often difficult to comment without giving everything away… I think it’s ok to assume that most people solve the problems before looking at the comments though 🙂

  7. Hi David! Excellent hard problem, the intermediate one was also practical too. However the one problem i have is glift showing a big red cross at the very first move of a wrong variation branch, instead of playing it to the end and then stating its wrong. I dont think thats desirable, of course others might find it useful but i wanted to bring it up anyway.