I took the index in the words, converted the range to binary, included three zeros, calculated the sha256 digest, took the primary part of the hexadecimal to convert it to binary, additional 3 zeros into the 8 digits in the binary and obtained 00000010011 which interprets to 19 in decimal. https://bookmark-master.com/story18835048/examine-this-report-on-bip39-mnemonic-phrase-tool