I took the index with the words, converted the variety to binary, included three zeros, calculated the sha256 digest, took the primary Section of the hexadecimal to transform it to binary, additional 3 zeros to the eight digits in the binary and acquired 00000010011 which interprets to 19 in decimal. https://thebookmarklist.com/story19420867/5-essential-elements-for-bip39-explained