I took the index in the words, converted the number to binary, added 3 zeros, calculated the sha256 digest, took the very first Element of the hexadecimal to transform it to binary, included 3 zeros towards the eight digits with the binary and obtained 00000010011 which translates to 19 in https://bookmarkinglive.com/story19839506/fascination-about-invalid-bip39-phrase