lib/numb/factorial.rb in numb-0.77.0 vs lib/numb/factorial.rb in numb-0.84.0

@@ -1,6 +1,17 @@
 class Integer
   def factorial
     return 1 if zero?
     (1..self).reduce(:*)
   end
+
+  def factorial?
+    divisors = self.divisors.sort
+    divisors.each_with_index do |d, i|
+      if divisors[i.succ] == d.succ
+        return true if d.factorial == self
+      else
+        return d.factorial == self
+      end
+    end
+  end
 end