I took the index in the words, converted the quantity to binary, additional 3 zeros, calculated the sha256 digest, took the first Section of the hexadecimal to transform it to binary, extra three zeros on the eight digits of the binary and got 00000010011 which interprets to 19 in decimal. https://bookmarkity.com/story18983883/the-ultimate-guide-to-bip39-seed-phrase-github