Update README.md

README.md

@@ -13,14 +13,15 @@ that are designed to be implemented by efficient immutable collections, along wi
 in developing the Certora Prover, we found that the reference implementation did not make the right performance
 tradeoffs for our use cases.
 
-Most `Set` and `Map` implementations, including the ones mentioned previously, are optimized primarily for speed of
-operations on single elements of the collection, e.g., adding an element to a `Set` or looking up a single value in a
-`Map`. However, in many use cases the more performance-critical operations are those that operate over the whole data
-structure, such computing set unions or intersection of two sets, or merging two maps.
+Most collection implementations, including the ones mentioned previously, are optimized primarily for speed of
+operations on single elements of the collection, e.g., adding an element to a `Set`, looking up a single value in a
+`Map`, getting a single `List` element by index. However, in many use cases the more performance-critical operations are
+those that operate over the whole data structure, such computing set unions or intersection of two sets, or merging two
+maps.
 
-The Certora Collections library provides `Set` and `Map` implementations which are optimized primarily for such
-operations.  Further, we optimize heavily for memory usage over speed of operations on single elements.  We also provide
-some additional features that we have found useful in the Certora Prover, such as efficient parallel operations.
+The Certora Collections library provides `Set` and `Map` and `List` implementations which are optimized primarily for
+such operations.  Further, we optimize heavily for memory usage over speed of operations on single elements.  We also
+provide some additional features that we have found useful in the Certora Prover, such as efficient parallel operations.
 
 ## Usage
 
@@ -31,8 +32,7 @@ The Certora Collections library is available on [JitPack](https://jitpack.io/#ce
 
 The API builds on the interfaces provided by [kotlinx.collections.immutable].  See The Kotlin Immutable Collections
 [proposal](https://github.com/Kotlin/kotlinx.collections.immutable/blob/master/proposal.md).  We provide some additional
-interfaces above the `PersistentMap` and `PersistentSet` interfaces provided by `kotlinx.collections.immutable`:
-
--
-
+methods beyond the `PersistentMap`, `PersistentSet`, and `PersistentList` interfaces provided by
+`kotlinx.collections.immutable`, in the `TreapMap`, `TreapSet`, and `TreapList` interfaces.
 
+To create instances of these collections, use the functions `treapMapOf`, `treapSetOf`, and `treapListOf`.