I took the index from the words, transformed the amount to binary, extra three zeros, calculated the sha256 digest, took the first Section of the hexadecimal to transform it to binary, added 3 zeros to the 8 digits with the binary and got 00000010011 which translates to 19 in decimal. https://geniusbookmarks.com/story18838932/the-basic-principles-of-bip39-passphrase-generator