I took the index on the words, converted the variety to binary, added 3 zeros, calculated the sha256 digest, took the very first part of the hexadecimal to convert it to binary, added a few zeros for the 8 digits on the binary and obtained 00000010011 which translates to 19 https://socialexpresions.com/story4327767/the-fact-about-bip39-seed-phrase-word-list-that-no-one-is-suggesting