I took the index on the words, transformed the selection to binary, added three zeros, calculated the sha256 digest, took the initial Component of the hexadecimal to transform it to binary, extra 3 zeros on the 8 digits of the binary and obtained 00000010011 which interprets to 19 in decimal. https://bookmarkinglive.com/story19592133/the-fact-about-bip39-seed-phrase-word-list-that-no-one-is-suggesting