-> 1. Reduce head (+ 1) to itself
-> 2. Reduce arg ((* ((/ 6) 2)) 4)
-> 1. Reduce head (* ((/ 6) 2))
-> 1. Reduce head * to itself
-> 2. Reduce arg ((/ 6) 2)
-> 1. Reduce head (/ 6) to itself
-> 2. Reduce arg 2 to itself
-> 3. Reduce ((/ 6) 2) to 3
-> 3. Reduce (* 3) to itself
-> 2. Reduce arg 4 to itself
-> 3. Reduce ((* 3) 4) to 12
-> 3. Reduce ((+ 1) 12) to 13
+> 1. Reduce head `(+ 1)` to itself
+> 2. Reduce arg `((* ((/ 6) 2)) 4)`
+> 1. Reduce head `(* ((/ 6) 2))`
+> 1. Reduce head `*` to itself
+> 2. Reduce arg `((/ 6) 2)`
+> 1. Reduce head `(/ 6)` to itself
+> 2. Reduce arg `2` to itself
+> 3. Reduce `((/ 6) 2)` to `3`
+> 3. Reduce `(* 3)` to itself
+> 2. Reduce arg `4` to itself
+> 3. Reduce `((* 3) 4)` to `12`
+> 3. Reduce `((+ 1) 12)` to `13`