diff --git a/examples/fac.scm b/examples/fac.scm
index b0969eb0..f52c6141 100644
--- a/examples/fac.scm
+++ b/examples/fac.scm
@@ -1 +1,6 @@
-(define (fac n) (if (= n 0) 1 (* n (fac (- n 1)))))
+(define (fac n) 
+  (if (= n 0) 
+    1 
+    (* n (fac (- n 1)))))
+
+(fac 10)