I took the index in the words, transformed the amount to binary, included 3 zeros, calculated the sha256 digest, took the 1st part of the hexadecimal to transform it to binary, added 3 zeros to your 8 digits from the binary and got 00000010011 which translates to 19 in decimal. https://postheaven.net/tiablexcen/mastering-your-copyright-protection-the-essential-overview-to-bip39-passphrases