Hikaru Problem 13
Hikaru no Go - Problem 13
This is found in the manga in chapter 104 Page 2. The problem is visible on the demo Board when Kurata Sensei asks "Are there any questions about this"?
For a solution and a discussion about this problem see: https://www.goproblems.com/problems/5575
This is found in Chapter 7 page 14. When Sai sees an older man trying to solve a problem on the Haze middle school festival set up by Tsutsui. The actual diagram shows one black stone more, which was obviously the first move tried by the man, so it's omitted from this problem diagram.
DuEm6: It seems there are 2 different problems on this page. One from Ch. 104 Pg. 2, shown in the goproblems.com link. The other one with the diagram is from Ch. 7 Pg 14, which is also Hikaru no Go - Problem 11.