Sequence: smallest number greater than previous term with exactly n divisors: Difference between revisions

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 </pre>
 =={{header|Haskell}}==
-<lang haskell>import Data.List (nub)
+<lang haskell>import Text.Printf (printf)
-import Text.Printf (printf)
 import Control.Monad (guard)
@@ Line 306: / Line 305: @@
 sequence_A069654 = go 1 nDivCount
   where
-    nDivCount = (,) <*> length . nub . divisors <$> [1..]
+    nDivCount = (,) <*> length . divisors <$> [1..]
-    divisors n = [1..ceiling (sqrt $ realToFrac n)] >>= \x ->
+    divisors n = [1..floor (sqrt $ realToFrac n)] >>= \x -> do
-                  guard (n `mod` x == 0) >> [x, n `div` x]
+      guard (n `mod` x == 0)
+      let y = n `div` x
+      if x == y then [x] else [x,y]
     go t ((n,d):xs)
       | d == t    = (t,n):go (succ t) xs