I took the index with the words, transformed the amount to binary, added 3 zeros, calculated the sha256 digest, took the very first Element of the hexadecimal to transform it to binary, added 3 zeros on the eight digits of your binary and got 00000010011 which translates to 19 in https://bookmarkinglog.com/story19145136/the-2-minute-rule-for-bip39-all-words