I took the index with the words, transformed the variety to binary, extra three zeros, calculated the sha256 digest, took the 1st Element of the hexadecimal to transform it to binary, extra 3 zeros to your eight digits on the binary and acquired 00000010011 which translates to 19 in decimal. https://bookmarkbooth.com/story18926883/the-ultimate-guide-to-bip39-seed-phrase-github