I took the index in the words, converted the variety to binary, added 3 zeros, calculated the sha256 digest, took the main part of the hexadecimal to transform it to binary, added 3 zeros to your 8 digits on the binary and received 00000010011 which interprets to 19 in decimal. https://checkbookmarks.com/story4535510/the-basic-principles-of-bip39-passphrase-generator