1, 3, 4 & 6 always tell the truth, and 2 & 5 always lie. 4's statements were in cryptogram form, and read: "3 tells the truth. Silver's atomic number is 47." Silver's atomic number IS 47, so we know that 4 always tells the truth. 4 says that 3 tells the truth, which must also be true. 3 says 2 is a liar, which we know must be true. 2 is a liar and says 1 is a liar, so we know 1 tells the truth. 1 calls 5 a liar, which is true. 5 lies and says 6 lies, so we know 6 tells the truth. If ONLY it were this easy to tell truth from lies :-)

The entire problem hinged around decoding 4's encrypted statement, thus verifying 1 person as a truth teller or a liar, and thereby establishing everybody else as one or the other. But even after successfully decoding 4's cryptogram, some people still missed this puzzle.

Winner: R. Narasimhan

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