Data update

Task/Arithmetic-derivative/Miranda/arithmetic-derivative.miranda

@@ -0,0 +1,24 @@
+main :: [sys_message]
+main = [Stdout (table 10 7 (map (show . lagarias) [-99..100])),
+        Stdout (lay (map ten_pow_m_div_7 [1..20]))]
+
+ten_pow_m_div_7 :: num->[char]
+ten_pow_m_div_7 m = "D(10^" ++ rjustify 2 (show m) ++ ") / 7 = " ++
+                    show (lagarias (10^m) div 7)
+
+table :: num->num->[[char]]->[char]
+table w cw ls = lay [concat (map (rjustify cw) l) | l <- group w ls]
+
+group :: num->[*]->[[*]]
+group n [] = []
+group n ls = take n ls : group n (drop n ls)
+
+lagarias :: num->num
+lagarias n = -lagarias (-n), if n<0
+           = sum [n div f | f <- factors n], otherwise
+
+factors :: num->[num]
+factors n = f n 2
+            where f n d = [], if d > n
+                        = d : f (n div d) d, if n mod d = 0
+                        = f n (d+1), otherwise