I took the index from the words, converted the range to binary, included a few zeros, calculated the sha256 digest, took the 1st Element of the hexadecimal to convert it to binary, additional three zeros towards the 8 digits of the binary and obtained 00000010011 which interprets to 19 in https://bookmarkity.com/story18997059/detailed-notes-on-copyright-wallet-seed-phrase-out-of-bip39