I took the index with the words, converted the selection to binary, added 3 zeros, calculated the sha256 digest, took the initial Element of the hexadecimal to convert it to binary, extra a few zeros to the eight digits with the binary and got 00000010011 which translates to 19 in https://socialstrategie.com/story4464898/the-5-second-trick-for-ledger-seed-phrase-bip39