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-* Here R, K, V is generated by linear transforms of input.
+* Here R, K, V is generated by linear transforms of input. Basically RWKV decomposes attention into R(target) * W(src -> target) * K(src). So I call R "receptance", and sigmoid means it's in 0~1 range.
 
 * The Time-mix is similar to AFT (https://arxiv.org/abs/2105.14103). There are two differences.