It's still a little difficult to find out what the minimum synthesis is for an active pattern, if you don't know already. I knew that five gliders was way too expensive, but how did I know that?mniemiec wrote:While adding a bit-spark is a well-known way to convert a ship into a bookend/century, there are already several known ways of creating one from only 3 gliders.Gustavo6046 wrote:Five-glider synthesis of C: ...
-- Well, first I checked Golly's Patterns/Life/Syntheses/two-glider-collisions.rle to make sure it couldn't be done with two gliders. Then I checked the LifeWiki and Mark's database under "century", but didn't see anything.
(I had the same problem with "phi spark" the other day, by the way. If no one has a publishable systematic set of stamp collections of these kinds of things, maybe it's time to put one together?)
Anyway, given that there wasn't a two-glider solution, my next idea was to look in my slow-salvo lookup table. @Gustavo, you might find that really useful. If a pattern shows up as an output in this table, it must be possible to build it with three or four gliders.
In this case, just do a text search for "century" in that linked message, and you'll find that there's a way to hit a boat with one glider to get a century. A boat can be synthesized with two more gliders, so there's one possible three-glider recipe... or actually, a couple of infinite groups of three-glider recipes, but they're all boringly similar.
Post a question here if there's something you don't understand, but really you shouldn't have any trouble finding the right boat+glider interaction -- I think at worst there are only 37 possibilities to check.