I took the index with the words, converted the variety to binary, extra 3 zeros, calculated the sha256 digest, took the 1st Element of the hexadecimal to transform it to binary, extra three zeros towards the 8 digits with the binary and obtained 00000010011 which interprets to 19 in decimal. https://bookmark-master.com/story18834956/5-simple-techniques-for-bip39-word-list-pdf