I took the index with the words, transformed the selection to binary, added 3 zeros, calculated the sha256 digest, took the first Section of the hexadecimal to transform it to binary, included three zeros into the 8 digits of your binary and acquired 00000010011 which interprets to 19 in decimal. https://bookmark-dofollow.com/story21733290/ledger-seed-phrase-bip39-no-further-a-mystery