I took the index of your words, converted the quantity to binary, added three zeros, calculated the sha256 digest, took the primary Component of the hexadecimal to transform it to binary, extra 3 zeros towards the 8 digits from the binary and got 00000010011 which interprets to 19 in decimal. https://nimmansocial.com/story8630917/not-known-facts-about-bip39-english-words