I took the index on the words, transformed the selection to binary, added 3 zeros, calculated the sha256 digest, took the very first Component of the hexadecimal to convert it to binary, included a few zeros to the 8 digits of your binary and got 00000010011 which translates to 19 https://socialicus.com/story4374686/top-guidelines-of-bip39-word-list-pdf