Bip39 Checksum. Now, at the subsequent degree we use these receiving and change key bunch to produce unique non-public keys. Use the above mentioned deliver non-public keys and chain code and pass them to the above mentioned described functionality kchild = kpar + hash(Kpar, cpar, i) to deliver unique keys. https://onelifesocial.com/story4475150/bip39-generator-https-linktr-ee-bip39-bip39-generator-an-overview