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Homework Help: Find the mysterious function that converts an 8 digit num to a 10 digit num

  1. Mar 10, 2008 #1
    This isn't a homework question. You guys are smart so I was wondering if you could somehow figure out the mysterious function f based on a few examples:

    f(26134914) = 2085386485
    f(26288902) = 2085920342
    f(26289423) = 2094236422
    f(26356300) = 2086136115

    What is "f" doing to convert that 8 digit number to a 10 digit? I'll produce more examples if needed

    Thanks for the help
    Last edited: Mar 10, 2008
  2. jcsd
  3. Mar 10, 2008 #2


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    Science Advisor

    Do you understand that there exist an infinite number of functions that will give those specific numbers? And no matter how many more example you give, there always exist a infinite number of functions that will give any finite set of specific values.
  4. Mar 10, 2008 #3

    Gib Z

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    Homework Helper

    If you give us k examples, we can construct a polynomial of k+1 degree (or higher), whose coefficients will be determined by a set of k+1 simultaneous linear equations which we could solve using Gaussian Elimination. Want to try it, cuz i dont :P
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