I took the index of your words, converted the quantity to binary, additional three zeros, calculated the sha256 digest, took the primary Element of the hexadecimal to convert it to binary, added three zeros to the eight digits of your binary and bought 00000010011 which interprets to 19 in decimal. https://bookmarkinglive.com/story19594673/little-known-facts-about-bip39-seed-phrase-list