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Posers and Puzzles

Posers and Puzzles

  1. Donation Pawnokeyhole
    Krackpot Kibitzer
    22 Jun '05 09:45
    I tried and solved my first (easy) Sudoku puzzle recently. It set me to wondering however: What is fewest number of initial entries into a 9 x 9 sudoku grid that permit such a puzzle to be solved? I suspect the number can be formally arrived at, but I don't know how. Any takers?

    Aiden
  2. Subscriber sonhouse
    Fast and Curious
    22 Jun '05 10:41
    On the sudoku site the puzzles there show either 3 or 4 numbers
    in each sub grid. So your only possiblity is 1 or 2 as smaller, not
    much of a range. 1 you could eliminate as allowing many solutions
    so the idea is to figure out if 2 in each grid could be set up
    to have only one solution, I think not. I think with 2 in each grid you
    have many more solutions so it looks to me like 3 and 4 are the
    minimum already.
  3. Standard member Palynka
    Upward Spiral
    22 Jun '05 12:25
    17 is the answer.
  4. Subscriber sonhouse
    Fast and Curious
    22 Jun '05 15:18
    Originally posted by Palynka
    17 is the answer.
    I had considered that, as well as 69 but the philosophical implications
    stymied me from venturing a valid logically unimpeachable arguement
    considered as a devils advocacy type of involvement with the
    fundamental numerical formulations.
  5. Standard member The Plumber
    Leak-Proof
    22 Jun '05 17:03
    Originally posted by Palynka
    17 is the answer.
    Huh uh...42. You should know that!
  6. Standard member XanthosNZ
    Cancerous Bus Crash
    22 Jun '05 19:07 / 1 edit
    + 3 + + + + 9 + +
    6 + + 4 + + + + +
    + + + + + + 7 + +
    + 7 + 2 9 + + + +
    + + + 3 + + + 6 +
    + + + + + + + 4 +
    4 + + + + 5 + 8 +
    + + + + 7 + 3 + +
    + + 1 + + + + + +

    OK I doubt this will work. But there is a 17 number setup with a unique solution. No 16 numbers setups with unique solutions have been discovered but they haven't been shown not to exist.

    EDIT: Well it worked kind of.
  7. Standard member The Plumber
    Leak-Proof
    22 Jun '05 19:59
    Oh, you meant 17 was the answer to the Soduku thing, I was thinking of Life, the Universe, and Everything.

    nevermind....
  8. Standard member Palynka
    Upward Spiral
    22 Jun '05 20:09
    Originally posted by The Plumber
    Oh, you meant 17 was the answer to the Soduku thing, I was thinking of Life, the Universe, and Everything.

    nevermind....
    The answer to that is, of course, the answer to the Soduku thing added to the number of months of the year and a lot of bad luck.

    That's how I got to the answer to the Soduku thing

    42 = 12 + 13 + X
    X = 17
  9. Subscriber sonhouse
    Fast and Curious
    22 Jun '05 22:14
    Originally posted by XanthosNZ
    + 3 + + + + 9 + +
    6 + + 4 + + + + +
    + + + + + + 7 + +
    + 7 + 2 9 + + + +
    + + + 3 + + + 6 +
    + + + + + + + 4 +
    4 + + + + 5 + 8 +
    + + + + 7 + 3 + +
    + + 1 + + + + ...[text shortened]... have been discovered but they haven't been shown not to exist.

    EDIT: Well it worked kind of.
    well that blows my 3 and 4 thing. The puzzle I saw on the sudoku
    site had 6 3's and 3 4's (30) It just seemed to allow more
    solutions if you had less occupied squares.
    So the key is the *position* in the squares.
  10. Subscriber sonhouse
    Fast and Curious
    22 Jun '05 22:34
    check out this site:
    http://www.shef.ac.uk/~pm1afj/sudoku/
  11. Subscriber sonhouse
    Fast and Curious
    22 Jun '05 22:36
    also this one:
    http://en.wikipedia.org/wiki/Sudoku#Rules_and_terminology
  12. Standard member orfeo
    Missing 285 + 1
    28 Jun '05 22:16
    Originally posted by sonhouse
    well that blows my 3 and 4 thing. The puzzle I saw on the sudoku
    site had 6 3's and 3 4's (30) It just seemed to allow more
    solutions if you had less occupied squares.
    So the key is the *position* in the squares.
    They've just started doing these in my local newspaper. The ones I've seen have 3 or 4 entries in SOME subsquares, but definitely not every subsquare.