I took the index of your words, converted the amount to binary, included three zeros, calculated the sha256 digest, took the 1st Section of the hexadecimal to transform it to binary, included 3 zeros for the 8 digits of the binary and obtained 00000010011 which interprets to 19 in decimal. https://totalbookmarking.com/story19062818/considerations-to-know-about-bip39-seed-phrase-generator