Feeds meet maths

January 23, 2009 Brian Mackie 1 Comment

Here’s a challenge (and quite beyond yours truly):  we have 600 news feeds in our list.  All of these feeds can be cross-referenced, stacked, or blocked from each other. 

For instance, you can combine feed A and feed B to make feed C.  Or, you can block feed B from feed A and make a new feed D.  Finally the feeds can be cross-referenced: articles that appear in feed A and feed B create new feed E.  You can use those 3 options in combination, and with as many feeds as you like, for example you can cross reference 10 feeds with another 10 feeds, from which you block another 5.

So the challenge is this (and ignoring the fact that not all feed combinations will make for sensible results): 

How many possible feed combinations can you make? Presumably there is a limit. Initially I thought 600-squared (360,000), but that doesn’t seem right, it must be more?

Unfortunately no prize for the brave and brilliant soul who can answer this question!  Though expect a bag of respect and your number may well make it into the Moreover “we have THIS many feeds” marketing blurb (saved for posterity ever after).

Filed under: web aggregation