I took the index in the words, transformed the variety to binary, added 3 zeros, calculated the sha256 digest, took the main Element of the hexadecimal to transform it to binary, included three zeros to your eight digits in the binary and got 00000010011 which interprets to 19 in decimal. https://bookmark-nation.com/story19311657/ledger-seed-phrase-bip39-no-further-a-mystery