No, it is a ternary search problem. EDIT: According to > https://en.wikipedia.org/w/index.php?title=Balance_puzzle&oldid=846801179 https://en.wikipedia.org/w/

No, it is a ternary search problem. EDIT: According to > https://en.wikipedia.org/w/index.php?title=Balance_puzzle&oldid=846801179 https://en.wikipedia.org/w/index.php?title=Balance_puzzle&ol... if you know that one coin is different from the others, with 3 weighings, you can even detect it among 13 coins (not just 12).