I took the index in the words, converted the quantity to binary, added three zeros, calculated the sha256 digest, took the very first Portion of the hexadecimal to convert it to binary, extra a few zeros for the 8 digits from the binary and got 00000010011 which interprets to 19 https://thegreatbookmark.com/story18874105/ledger-seed-phrase-bip39-no-further-a-mystery