It's a parlor trick because something like "1, * × 2 ..." is much more sensible. Heck, it isn't even longer, if we're talking about saving keystrokes. It's still more syntax than I'm looking for from a language, but "initial, update rule, continue infinitely" does not give me that immediate "oh wtf, what other magic is going to happen with other values?" reaction I describe from trying to divine update rules from raw numbers.
It is also immediately obvious how to use this for other patterns, immediately obvious how to compose it, and just generally experiences all the benefits things get from not being special cases.
