I took the index with the words, transformed the variety to binary, extra 3 zeros, calculated the sha256 digest, took the initial Portion of the hexadecimal to convert it to binary, included 3 zeros to your eight digits of your binary and received 00000010011 which interprets to 19 in decimal. https://bookmarkplaces.com/story18759889/ledger-seed-phrase-bip39-no-further-a-mystery