Anyone know what the pattern is behind the number puzzle on stage 23? 15 55 120 210. I knew the answer because I read it on here by accident a week or so ago and it stuck in my head. I would never have solved it directly though. Even with the answer I can't find an elegant pattern.
The only thing I can see they have in common is multiples of 5: 3, 11, 24, 42. And I can spot kind of a pattern in the way they grow, but it's not neat. It goes 8, 13, 18, which are all plus 5. As in 3+8=11, 11+13=24, 24+18=42.
It has to be neater than that. I mean, after all those easy number puzzles, why suddenly one that ordinary non-math people would have a hard time solving? It seems a bit harsh for a game. If I'd been playing this game in isolation, and there weren't a forum like this where you could find the answer, I probably would have got past that stage, but only by trying every multiple of 5 from about 180 up.