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

1. Mar 10, 2008

### bobthebanana

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. Mar 10, 2008

### HallsofIvy

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.

3. Mar 10, 2008

### Gib Z

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