I took the index of your words, transformed the number to binary, included 3 zeros, calculated the sha256 digest, took the main part of the hexadecimal to transform it to binary, extra a few zeros on the eight digits of the binary and received 00000010011 which translates to 19 in https://bookmark-master.com/story18834996/helping-the-others-realize-the-advantages-of-bip39-seed-phrase-mnemonics-generator