I took the index of your words, converted the quantity to binary, extra three zeros, calculated the sha256 digest, took the primary Section of the hexadecimal to convert it to binary, additional three zeros to your eight digits of the binary and acquired 00000010011 which translates to 19 in decimal. https://bookmarkusers.com/story18630381/the-basic-principles-of-bip39-passphrase-generator