I took the index with the words, transformed the amount to binary, included a few zeros, calculated the sha256 digest, took the primary Portion of the hexadecimal to transform it to binary, added 3 zeros into the 8 digits with the binary and obtained 00000010011 which translates to 19 in https://bookmarkingdepot.com/story19404938/not-known-factual-statements-about-bip39-explained