I took the index from the words, transformed the variety to binary, additional 3 zeros, calculated the sha256 digest, took the main Section of the hexadecimal to transform it to binary, extra a few zeros for the eight digits with the binary and got 00000010011 which translates to 19 in https://bookmarkproduct.com/story19041168/top-guidelines-of-bip39-word-list-pdf