Sure, this was a class at an American university, the context of those particular numbers is important as an example, but the exercise likely transfers to other relevant dates in other countries. At the core of it though is that arguably there are IPs (numbers) in any org that might be worth committing to memory because systems can and do fail, and for humans it seems to me that encoding IPv4 is inherently easier than encoding IPv6. My (untested) hypothesis is that this may be at least somewhat of a contributing factor to the slowness of IPv6 adoption (IMO the other more prevalent one being the market factors re. IPv4 scarcity). I just thought it was an interesting parallel to share.