I took the index with the words, transformed the number to binary, added three zeros, calculated the sha256 digest, took the initial Component of the hexadecimal to transform it to binary, included three zeros for the eight digits from the binary and got 00000010011 which translates to 19 in decimal. https://socialmediastore.net/story19437667/the-basic-principles-of-bip39-passphrase-generator