I took the index from the words, transformed the quantity to binary, extra 3 zeros, calculated the sha256 digest, took the very first part of the hexadecimal to convert it to binary, included three zeros into the eight digits from the binary and acquired 00000010011 which interprets to 19 in https://yoursocialpeople.com/story4525355/the-fact-about-valid-bip39-seed-phrase-that-no-one-is-suggesting