I took the index on the words, converted the selection to binary, included 3 zeros, calculated the sha256 digest, took the first Portion of the hexadecimal to transform it to binary, additional three zeros to your eight digits in the binary and obtained 00000010011 which interprets to 19 in decimal. https://myfirstbookmark.com/story18832674/the-fact-about-valid-bip39-seed-phrase-that-no-one-is-suggesting