I took the index with the words, transformed the variety to binary, added three zeros, calculated the sha256 digest, took the first Component of the hexadecimal to convert it to binary, added a few zeros to the 8 digits from the binary and obtained 00000010011 which translates to 19 in https://ztndz.com/story21942692/not-known-factual-statements-about-bip39-explained