I took the index of the words, converted the range to binary, additional three zeros, calculated the sha256 digest, took the initial Element of the hexadecimal to convert it to binary, extra a few zeros for the 8 digits on the binary and obtained 00000010011 which interprets to 19 in https://siambookmark.com/story18863434/facts-about-bip39-seed-phrase-word-list-revealed