I took the index in the words, converted the number to binary, additional 3 zeros, calculated the sha256 digest, took the main part of the hexadecimal to convert it to binary, additional three zeros towards the 8 digits of your binary and received 00000010011 which interprets to 19 in decimal. https://thekiwisocial.com/story4245665/top-guidelines-of-bip39-word-list-pdf