# Report 4/27 ### Reinforcement Learning: An Introduction (2e) [Contraction mapping](https://drive.google.com/file/d/172g34-l4C0qnsE-Gu9y5XQ__PkmoJ1Z8/view?usp=sharing)
×
Sign in
Email
Password
Forgot password
or
By clicking below, you agree to our
terms of service
.
Sign in via Facebook
Sign in via Twitter
Sign in via GitHub
Sign in via Dropbox
Sign in with Wallet
Wallet (
)
Connect another wallet
New to HackMD?
Sign up