# Five Hundred And One Tesuji Problems / Errata

These errata refer to 'First Printing October 2005'. About half of the typos have been corrected in the second printing (October 2016) but the most serious errors (in the problems) remain. More than 20 of the problems are simply wrong, and in addition two are duplicates and another two so similar as to be practically duplicates. Skip to the positions at the end of the list to see the wrong problems.

Wrong: If White ataries with 3, Black simply connects with 3.
Right: If White ataries with 2, Black simply connects with 3.
Wrong: White no longer needs to worry about the exchange of White A for Black B.
Right: Black no longer needs to worry about the exchange of White A for Black B.
Wrong: If White now ataries with 4 in Dia.2, White will double atari with 5.
Right: If Black now ataries with 4 in Dia.2, White will double atari with 5.
Wrong: After the sequence to White 9, Black loses the capturing race.
Right: After the sequence to White 7, Black loses the capturing race.
Wrong: If Black attacks at A, defending with Black B is sente.
Right: If Black attacks at A, defending with White B is sente.
p35, label for problem 62.
Wrong: Black to play.
Right: White to play.
Wrong: White should limit his loss by playing 4 in Dia. 2.
Right: White should limit his loss by playing 2 in Dia. 2.
Wrong: If White answer Black 1 with 2 in Dia.2, Black blocks with 3.
Right: If White answers Black 1 with 2 in Dia.2, Black blocks with 3.
Wrong: White has linked up his stones and secured a large corner.
Right: Black has linked up his stones and secured a large corner.
p72, last line.
Wrong: White gets ma ladder with 3 to 7 and captures some black stones.
Right: White gets a ladder with 3 to 7 and captures some black stones.
p80, answer 139, label for Dia. 2.
Wrong: Failure
Right: Variation
p96.
Wrong: Answer to Problem 175 (tsuke)
Right: Answer to Problem 172 (tsuke)
Wrong: ...weak groups after he connect with 6 (above 4).
Right: ...weak groups after he connects with 6 (above 4).
p118, answer 214, label for Dia. 2.
Wrong: Failure
Right: Variation
Wrong: The clamp of 1 in Dia. 2 enables Black...
Right: The clamp of 1 in Dia. 1 enables Black...
Wrong: ...Black squeezes with 3 and 5, then extend to 7.
Right: ...Black squeezes with 3 and 5, then extends to 7.
p143, problem 269.
Wrong: How can Black save his stone on the right side?
Right: How can Black save his stones on the right side?
p144, answer 265, label for Dia. 2.
Wrong: Failure
Right: Variation
p151, problem 281, label.
Wrong: How Black save his four stones on the right?
Right: How can Black save his four stones on the right?
Wrong: Answering White 3 with Black 4 in Dia. 2 lets White liink up without any problems.
Right: Answering White 3 with Black 4 in Dia. 2 lets White link up without any problems.
Wrong: White now has to connects with 8
Right: White now has to connect with 8
p165, answer 296, label for Dia. 2
Wrong: Variation
Right: Failure
p168, answer 301, label for Dia. 2
Wrong: Failure
Right: Variation
p168 & p169.
p177, answer 315, label for Dia. 2
Wrong: Failure
Right: Variation
Wrong: If White captures with A, Black ataries with B ...
Right: If Black captures with A, White ataries with B ...
Wrong: White blocks with4.
Right: White blocks with 4.
Wrong: The White stones are confined to the corner
Right: The Black stones are confined to the corner
p181.
p199, problem 360.
Wrong: ... how can Black capture the five marked black stones?
Right: ... how can White capture the five marked black stones?
p201, answer 360, label for Dia. 2
Wrong: Continuation
Right: Variation
p204, answer 365, label for Dia. 3
Wrong: Failure
Right: Variation
Wrong: After White ataries with 6, White can't capture the stones at 2 because his stones will be recaptured in a snapback.
Right: After White ataries with 6, Black can't capture the stone at 2 because his stones will be recaptured in a snapback.
Wrong: If Black jumps to 1 in Dia. 3, Black can take profit in the corner with 3.
Right: If Black jumps to 1 in Dia. 3, White can take profit in the corner with 2.
p215, problem 391, label.
Wrong: How Black link up his stones?
Right: How can Black link up his stones?
p215; problems 392, & 394: labels.
Wrong: How Black link up all his stones?
Right: How can Black link up all his stones?
Label for 3rd diagram.
Wrong: Dia. 2. Continuation 2
Right: Dia. 3. Continuation 2
Label for 4th diagram.
Wrong: Dia. 3. Failure
Right: Dia. 4. Failure
4th diagram upside down.
p237, problem 426.
Wrong: If Black captures with 1 in Dia.3, White draws back to 3.
Right: If Black captures with 2 in Dia.3, White draws back to 3.
p239, problem 433.
There should be an extra White stone at S16 - see answer diagrams p242
Wrong: Black 1 in Dia 2 is a mistake.
Right: White 1 in Dia 2 is a mistake.
Wrong: If Black hanes with 2, Black jumps to 3
Right: If Black hanes with 2, White jumps to 3
Wrong: If Black defends with 4, Black 5 isolates the Black stone on the left.
Right: If Black defends with 4, White 5 isolates the Black stone on the left.
Wrong: Although White has captured two stones, White ends with a solid eye and sente.
Right: Although Black has captured two stones, White ends with a solid eye and sente.
Wrong: ...White can save his stones on the right and kill three of Black's with the hane of 3, but Black captures...
Right: ...White can save his stones on the right and kill three of Black's with the hane of 2, but Black captures...
Wrong: If White defends against this move, Black connect at B and White's five stones on the left are in trouble.
Right: If White defends against this move, Black connects at B and White's five stones on the left are in trouble.
p279, problem 494.
Wrong: One of the White stones is misplaced. Should be a two space jump, instead of the one space jump.
Right: See position in the answer p281

Actual mistakes in problems:

Problem 1
Problem 1
Black links up only conditional on a 2 stage ko in his favour (common tesuji missed in answers).
ko
Problem 3
Problem 3
Black requires a small amount of support on the top in order to live. Black will need to cut below 6 or his stones will still die. The book has 7 at 8, which is even more painful (atari at a in this diagram gets Black out with sente, but does work if White has already played atari at b, as in the answers).
Problem 15
Problem 15
The answer assumes White must capture, which is simply not true. White has resources underneath and a complicated fight ensues. After 9, the stone at 4 is dead, and Black can reply to a with b, so this seems like a good fight for Black. White can also try the diagonal move (a), but the result is much the same.
Problem 31
Problem 31
Black can't save both stones like the question asks,. This rather obvious response from White is omitted.
Problem 118
Problem 118
The book only covers one possible way White could connect. The other way, Black can make some shape, and has good aji in the corner. This certainly doesn't seem like the "two eyes" that the question proposes, however.
Problem 146
Problem 146
The book claims that B will "easily make two eyes". If White fights, as the problem stands, this is not as trivial as it makes out. It's important for Black to have some support on the outside, or he will be forced to run (see below).
fixed?
Problem 149
Problem 149
The book doesn't cover Black's strongest resistance, which is to stand with the attached stone. White appears to be able to live in the corner, but ruins the outside stones in the process. Given in the book, White strengthens rather than destroys the outside, this seems like a mistake.
Problem 216
White either needs the ladder, or an extra stone. If not, the solution line becomes problematic.
Problem 216 (continuation)

Black makes miai of a (ladder) and b (net).

Problem 219
Problem 219
The solution omits White's moves after 5. In fact, these moves are so problematic that Black has no good response; the corner appears to become ko at best. Black should play 3 at 4, which captures cleanly using a common tesuji.
Problem 219, continuation.

Black will have to fight the ko at 2. There are no extra liberties in the corner.

Problem 219, continuation 2.

Black must take all of the corner liberties in order to avoid fighting the ko, but this is impossible.

Problem 219, continuation 2 continued.

Black can easily find his stones in trouble if he tries to kill directly.

Problem 219, Solution

Black can, however, win by the famous tesuji at 3. Black is in no danger here.

Problem 220
Problem 220
This one is a simple bad play in the solution. White captures at a, letting Black get more points in the corner than deserved.
Problem 242
Problem 242
The book does not mention what happens when Black plays at 4 instead of a. In fact, White dies, although black can connect into the corner.
Problem 242, oops
Problem 242, proposed modification

With the extra stones here, White is able to play the standard 2 stone edge squeeze and win.

Problem 279
This is a duplicate of problem 49.
Problem 281
Problem 281
This problem has many answers; none seems better or worse than the "correct" ones without being told more about the situation. The addition of the marked stones makes the answer unique, although different from the solution given (that solution doesn't seem to offer many advantages).
Problem 306
Problem 306
This problem has many, many variations depending on Black's initial response (some of which are marked above). There doesn't seem to be any sensible way to reconcile these possibilities, and most of them remove the sequence which presumably is the point of the problem, so the problem might be modified to have the first two moves of the solution already played.
Problem 324
Problem 324
The "correct" solution is shown. The book claims that the three white stones are dead. However...
White can connect

So this would be considered a broken problem.

Problem 338
Problem 338
The "correct" solution is shown. The book claims that Black has gotten a good result by connecting. However...
Black can kill

In fact, White cannot even kill Black if Black plays this move!

Problem 354 is almost identical to Problem 218 (the only difference is that Black has has an extension in the earlier problem).
Problem 377
Problem 377
One of the answer diagrams suggests playing as above, aiming to kill the White stones. However, this sequence simply doesn't work. It is unclear to me where 5 should be played.
Problem 377, Continuation

B simply doesn't appear to be able to even create a ko, however.

Problem 377, Continuation 2

What a disaster. With some support, Black should be able to recover, but the problem suggests such support is not available.

Problem 377, Alternative

Perhaps the answer is to play this way. Black can live or run, so eventually White will have to live, too. Is this a good result?

Problem 395
Problem 395
The book misses the neat move at 2.
Problem 395

Black is able to live in the corner in sente, but White keeps the outside stones attackable. White can play 2 at a to make an unfightable ko. Likewise, Black can throw in with 1 at 3 to make another ko. However, both kos are 2 stage in the favour of the opponent.

Problem 403
Problem 403
The book suggests playing this ko, but Black can kill the stones outright.
Problem 403, White dies

White cannot get 3 liberties in sente, so the cutting stones will die.

Problem 407
Problem 407
The book omits Black's strongest response at 2 here.
Problem 407

White is able to cut, but Black can sacrifice some stones for an arguably better result: Black has some potential to attack the lower group now.

Problem 445
Problem 443 is extremely similar to Problem 370 (same tesuji, different surrounding position).
Problem 445
The book neglects this important sequence. White must connect above 9 and let Black take the stone.
Problem 462
Problem 462
The book answer is wrong, leaving black with a terrible result since White can immediately cut at 8 and B loses the corner.
Problem 462, Better

Black should of course play an edge squeeze...

Problem 462, Continuation

This way (4 at 1), Black is still able to capture the stone at 6.

Problem 479
Problem 479
It is rather unclear if playing 3 at 6 is worse.
Problem 479

White could fight here also by playing 4 at 5, and this way White might be able live in the corner before the fight starts -- but the fight then sees two strong Black groups against one weak White group. Either way, it seems this sequence ought to be covered in the answers.

Five Hundred And One Tesuji Problems / Errata last edited by rogermorgan on May 3, 2020 - 17:11