I took the index on the words, transformed the amount to binary, added three zeros, calculated the sha256 digest, took the 1st Component of the hexadecimal to convert it to binary, added three zeros to the 8 digits of your binary and bought 00000010011 which translates to 19 in decimal. https://meshbookmarks.com/story19084364/the-fact-about-valid-bip39-seed-phrase-that-no-one-is-suggesting