I took the index on the words, converted the quantity to binary, extra three zeros, calculated the sha256 digest, took the first Section of the hexadecimal to convert it to binary, included 3 zeros to the 8 digits in the binary and got 00000010011 which interprets to 19 in decimal. https://bookmarkstumble.com/story20513764/bip39-seed-phrase-fundamentals-explained