I took the index of the words, converted the number to binary, extra a few zeros, calculated the sha256 digest, took the main part of the hexadecimal to transform it to binary, included three zeros to your 8 digits of the binary and received 00000010011 which translates to 19 in https://explorebookmarks.com/story18872129/new-step-by-step-map-for-ledger-seed-phrase-bip39