I took the index of your words, converted the selection to binary, extra 3 zeros, calculated the sha256 digest, took the initial Element of the hexadecimal to convert it to binary, extra three zeros towards the eight digits on the binary and got 00000010011 which interprets to 19 in decimal. https://tealbookmarks.com/story18841512/not-known-factual-statements-about-bip39-explained