I took the index of the words, converted the variety to binary, additional 3 zeros, calculated the sha256 digest, took the first Element of the hexadecimal to transform it to binary, included 3 zeros into the eight digits from the binary and received 00000010011 which translates to 19 in decimal. https://bookmark-vip.com/story19680071/bip39-seed-phrase-fundamentals-explained