I took the index on the words, converted the variety to binary, additional three zeros, calculated the sha256 digest, took the first Element of the hexadecimal to convert it to binary, extra 3 zeros to your 8 digits on the binary and got 00000010011 which translates to 19 in decimal. https://madbookmarks.com/story18944738/5-simple-techniques-for-bip39-seed-phrase