I took the index from the words, converted the range to binary, additional 3 zeros, calculated the sha256 digest, took the initial Section of the hexadecimal to transform it to binary, included three zeros to your eight digits of the binary and received 00000010011 which interprets to 19 in decimal. https://allyourbookmarks.com/story18929534/top-guidelines-of-bip39-word-list-pdf