I took the index with the words, transformed the number to binary, included three zeros, calculated the sha256 digest, took the very first A part of the hexadecimal to transform it to binary, extra 3 zeros on the 8 digits of the binary and got 00000010011 which interprets to 19 https://bookmark-master.com/story19178759/the-ultimate-guide-to-bip39-seed-phrase-mnemonics-generator