I took the index with the words, transformed the variety to binary, added 3 zeros, calculated the sha256 digest, took the primary Portion of the hexadecimal to transform it to binary, extra 3 zeros to your eight digits of your binary and bought 00000010011 which interprets to 19 in decimal. https://bookmarkfox.com/story4402995/the-basic-principles-of-bip39-passphrase-generator