Re: [Haskell-begin] Alternating sequence

Dirk Markert wrote:

I am trying to generate the following list: 2, 3, 5 -- and then alternating (+2) resp (+4) -- 7, 11, 13, 17, 19, 23

I came up with the following solution 2:3:unfoldr (\(a,b) -> Just (a,(a+b, if b == 2 then 4 else 2))) (5,2)

Are there easier ways to generate the desired list?

Use a left scan result = 2:3:scanl (+) 5 (cycle [2,4]) Regards, apfelmus