I took the index on the words, transformed the number to binary, added 3 zeros, calculated the sha256 digest, took the initial Portion of the hexadecimal to transform it to binary, added 3 zeros to your 8 digits with the binary and got 00000010011 which translates to 19 in decimal. https://bookmarkcitizen.com/story19477905/not-known-factual-statements-about-bip39-explained