I took the index from the words, transformed the selection to binary, additional 3 zeros, calculated the sha256 digest, took the first part of the hexadecimal to transform it to binary, included a few zeros into the 8 digits with the binary and got 00000010011 which translates to 19 in https://getsocialselling.com/story4199243/ledger-seed-phrase-bip39-no-further-a-mystery