I took the index from the words, transformed the variety to binary, included 3 zeros, calculated the sha256 digest, took the first Section of the hexadecimal to transform it to binary, additional three zeros into the 8 digits of the binary and got 00000010011 which interprets to 19 in decimal. https://bookmarkforest.com/story18738875/the-basic-principles-of-bip39-passphrase-generator