Puzzle: Count from 1 to 10 in base negative 2.
Edited for (some) clarity: Count in base -2, starting from 1, taking 9 steps.
Edited for (some) clarity: Count in base -2, starting from 1, taking 9 steps.
The definition of writing something in base n is that you are expressing a number it using n unique values for each digit. Using these digits, there is a way of utilizing the space maximally to write any positive integer which is the above method of packing the values. Simply using n unique values and having each digit #d represent the power n^d.
For base -2, using -2 unique symbols is clearly nonsense. Assigning each digit a power of -2 and allowing for symbols 0 or 1 for each digit is actually just base 2, exactly like how gray code is base 2. It's interesting that its a form of base 2 that has an implicit sign-bit, but its also somewhat strange of a property since it ends up with twice as many negative numbers as positive numbers for any set number of bits.
Microsoft should clearly hire me.
Otherwise, I don't have a problem with you giving us your answer, although others might like to think about it first. Of course, the question has had so few upvotes, no one is likely to see it.
edit: also, I had a different idea of what "taking a step" would mean. my solution: http://pastie.org/1987386
Can you do it without negative signs?