I took the index of the words, transformed the amount to binary, included 3 zeros, calculated the sha256 digest, took the main A part of the hexadecimal to convert it to binary, added 3 zeros to your eight digits on the binary and acquired 00000010011 which translates to 19 in https://thejillist.com/story8909079/not-known-facts-about-bip39-english-words