Update README.md

README.md

@@ -1,6 +1,6 @@
 # The RWKV Language Model
 
-## RWKV v2 RNN
+## RWKV v2 RNN: Language is in O(1)
 
 RWKV v2 is a RNN which can also be directly trained like a GPT transformer.
 
@@ -16,6 +16,8 @@ Write out the formulas for "token at pos 2" and "token at pos 3" and you will ge
 * a and b: EMAs of kv and k.
 * c and d: a and b combined with self-attention.
 
+kv / k is the memory mechanism. The token with high k can be remember for a long period, if W is close to 1 in the channel.
+
 The pseudocode (execution from top to bottom):
 
 ![RWKV-v2-RNN](RWKV-v2-RNN.png)