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I'm note sure if this is mathematical, however I know that there's an area of maths about folding. And regardless, this seems like an interesting question that I have no idea how to solve.

I am designing a 5 day paper timetable for university that I will keep in my pocket so I know where and when my classes are. My current timetable is a table with days as columns, hours as rows and cells being classes. However when I came to fold this I found that it was awkward. In order to fold it small enough to fit in my pocket I needed to fold it many times, which in turn meant that to view some parts of the time table I needed to unfold it many times.

How can I fold a timetable so that to view any part requires the least amount of unfolding?

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It's an interesting question, but to make it amenable to mathematical analysis you'll need to specify more precisely what you're trying to achieve. It's not clear how "to view any part requires the least amount of unfolding" is to be interpreted. For instance, you could minimize the sum (and hence the average) over all pages of the number of unfolding operations you need to view it, or you could minimize the sum of the squares of these numbers if you feel that requiring 5 operations for one particular page is worse than requiring one more operation each for some of the other pages. – joriki Feb 17 '11 at 14:21
Also, you might want to say something about the options that should be considered. Is the whole timetable one long strip and you want to fold it along axes perpendicular to its length? Or is it more square-shaped and you want to consider folding operations parallel to both axes? Or perhaps you even want to allow diagonal or even arbitrary folding axes? – joriki Feb 17 '11 at 14:23
I think it's reasonable to minimize the expected number of unfoldings necessary to view any cell (possibly weighted by how often you think you need to view each cell). We still need more information along the lines of how many rows, how many columns, what kinds of folds are allowed... – Qiaochu Yuan Feb 17 '11 at 15:04

If you can make the overall form a horizontal strip that only needs to be folded vertically, then accordion folding (score at equal intervals, fold starting at one end, alternately forward and backward) will allow you to see any panel with a single unfolding.

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