Added Factorial with Lua

math/factorial/Lua/Factorial.lua

@@ -0,0 +1,17 @@
+--recursive function to factorial
+function fat(num)
+  --if number < 0 dont have factorial
+  if num<0 then
+    return "Dont have factorial"
+  end
+  --factorial of 1 and 0 is 1
+  if num == 1 or num == 0 then
+    return 1
+  end
+  --factorial of num > 1 is num*factorail of num-1
+  return num*fat(num-1)
+
+
+end
+--print factorial of 5
+print(fat(4))