I took the index with the words, converted the amount to binary, included 3 zeros, calculated the sha256 digest, took the first A part of the hexadecimal to transform it to binary, added 3 zeros on the eight digits of the binary and got 00000010011 which interprets to 19 in https://bookmarklinking.com/story4996361/not-known-factual-statements-about-bip39-explained