Chowla numbers: Difference between revisions

import Data.List (intercalate)

 

sumFactors = product . map f

where f (n, count) = foldr (\p s -> s + unPrime n^p) 1 [1..count]

 

chowla 1 = 0

chowla n = sumFactors (factorise n) - 1 - n

 

chowlaPrime 1 = False

chowlaPrime n = chowla n == 0

 

chowlaPerfectNum 1 = False

chowlaPerfectNum n = chowla n == pred n

 

chowlaPrimes = go 0 [1..]

where