I took the index with the words, transformed the quantity to binary, included three zeros, calculated the sha256 digest, took the 1st Component of the hexadecimal to transform it to binary, additional 3 zeros to the 8 digits of your binary and bought 00000010011 which translates to 19 in decimal. https://privatebookmark.com/story19494148/facts-about-bip39-seed-phrase-word-list-revealed