lib/numb/mobius.rb in numb-0.170.0 vs lib/numb/mobius.rb in numb-0.181.0

@@ -1,10 +1,17 @@
 # coding: utf-8
 class Integer
   def mobius
    return if self < 1
-   ω < Ω  ? 0 : (-1)**(Ω)
+   ω < Ω  ? 0 : liouville
   end
 
   alias :möbius :mobius
   alias :μ :mobius
+
+  # TODO: Consider Deléglise and Rivat's "Computing the Summation of the
+  # Mőbius Function", Experimental Mathematics, Vol. 5 (1996), No. 4
+
+  def mertens
+    (1..self).map(&:μ).reduce(:+)
+  end
 end