-1. Substitution; using alpha-conversion and other strategies
-1. Conversion versus reduction
-1. Eta reduction and "extensionality"
-1. Different evaluation strategies (call by name, call by value, etc.)
-1. Strongly normalizing vs weakly normalizing vs non-normalizing; Church-Rosser Theorem(s)
-1. Lambda calculus compared to combinatorial logic<p>
-1. Encoding pairs (and triples and ...)
-1. Encoding booleans
-1. Church-like encodings of numbers, defining addition and multiplication
-1. Defining the predecessor function; alternate encodings for the numbers
-1. Homogeneous sequences or "lists"; how they differ from pairs, triples, etc.
-1. Representing lists as pairs
-1. Representing lists as folds
-1. Typical higher-order functions: map, filter, fold<p>
-1. Recursion exploiting the fold-like representation of numbers and lists (deforestation, zippers)
-1. General recursion using omega
-1. The Y combinator(s); more on evaluation strategies<p>
-1. Introducing the notion of a "continuation", which technique we'll now already have used a few times
+2. Substitution; using alpha-conversion and other strategies
+3. Conversion versus reduction
+4. Eta reduction and "extensionality"
+5. Different evaluation strategies (call by name, call by value, etc.)
+6. Strongly normalizing vs weakly normalizing vs non-normalizing; Church-Rosser Theorem(s)
+6. Lambda calculus compared to combinatorial logic
+
+7. Encoding pairs (and triples and ...)
+8. Encoding booleans
+9. Church-like encodings of numbers, defining addition and multiplication
+10. Defining the predecessor function; alternate encodings for the numbers
+11. Homogeneous sequences or "lists"; how they differ from pairs, triples, etc.
+12. Representing lists as pairs
+13. Representing lists as folds
+14. Typical higher-order functions: map, filter, fold
+
+15. Recursion exploiting the fold-like representation of numbers and lists ([deforestation](http://en.wikipedia.org/wiki/Deforestation_%28computer_science%29), [zippers](http://en.wikipedia.org/wiki/Zipper_%28data_structure%29))
+16. General recursion using omega
+17. The Y combinator(s); more on evaluation strategies
+
+18. Introducing the notion of a "continuation", which technique we'll now already have used a few times