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diff --git a/topics/week2_lambda_intro.mdwn b/topics/week2_lambda_intro.mdwn
index 3718d31..091e123 100644 (file)
--- a/topics/week2_lambda_intro.mdwn
+++ b/topics/week2_lambda_intro.mdwn
@@ -270,7 +270,7 @@ For some lambda terms, it is easy to see what function they represent:
 simply returns `M`: `((\x x) M) ~~> M`.
 
 > `(\x (x x))` duplicates its argument (applies it to itself):
-`((\x (x x)) M) ~~> (M M)` <!-- **M** or &omega;; W is \uv.uvv -->
+`((\x (x x)) M) ~~> (M M)` <!-- **M** or &omega;; W is \uv.uvv, L is \uv.u(vv) -->
 
 > `(\x (\y (y x)))` reorders its two arguments:
 `(((\x  (\y (y x))) M) N) ~~> (N M)` <!-- **T**; C is \uvx.uxv -->