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3-nines clock

  1. Sep 22, 2013 #1

    Simon Bridge

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    I come across some odd stuff online....


    ... OK there's a typo for the 5 ... should be ##\small [\sqrt{9}]!-(9/9)## and the one for 7 looks a bit forced...
    What I'm wondering is if there are other sets that do something like this ... i.e. so for a given integer Z, we can find another integer z<Z so that the integers â‰ĪZ can be represented using the same n (integer) instances of z in each case.

    It'll probably help of Z is something with lots of divisors ... i.e. Z= oh I dunno... 12.
    Or is it just a case of "given sufficient cleverness" - which is to say that there are so many legitimate mathematical operations that it is always possible to create this effect?

    Millenialists take note: hold the clock upside down and all the numbers are made out of three 6's.
  2. jcsd
  3. Sep 22, 2013 #2


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    I'm sure there are lists of that somewhere.

    Those two are always possible.
    9 is nice, as you can choose between 9 and 3 via the square root.
    With small even numbers, it is tricky to get large odd numbers.
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