Another update from ingydotnet^djgoku

Task/Left-factorials/Elixir/left-factorials.elixir

@@ -0,0 +1,20 @@
+defmodule LeftFactorial do
+  def calc(0), do: 0
+  def calc(n) do
+    {result, _factorial} = Enum.reduce(1..n, {0, 1}, fn i,{res, fact} ->
+      {res + fact, fact * i}
+    end)
+    result
+  end
+end
+
+Enum.each(0..10, fn i ->
+  IO.puts "!#{i} = #{LeftFactorial.calc(i)}"
+end)
+Enum.each(Enum.take_every(20..110, 10), fn i ->
+  IO.puts "!#{i} = #{LeftFactorial.calc(i)}"
+end)
+Enum.each(Enum.take_every(1000..10000, 1000), fn i ->
+  digits = LeftFactorial.calc(i) |> to_char_list |> length
+  IO.puts "!#{i} has #{digits} digits"
+end)