I took the index from the words, transformed the range to binary, additional three zeros, calculated the sha256 digest, took the first Element of the hexadecimal to convert it to binary, extra three zeros to the 8 digits of your binary and obtained 00000010011 which interprets to 19 in decimal. https://thebookmarkage.com/story19121611/new-step-by-step-map-for-ledger-seed-phrase-bip39