Bip39 ian coleman https://www.empowher.com/user/4550298 Checksum generation: A checksum is generated from this entropy employing SHA-256 hashing, which will help validate the mnemonic's integrity later on. For words that only have 3 letters, there is not any 4th letter. For instance Using the word “add”, there isn't any additional letters afterwards https://socialskates.com/story21384300/bip39-npm-a-simple-key-for-bip39-github-unveiled-https-linktr-ee-bip39