I took the index of the words, transformed the number to binary, added 3 zeros, calculated the sha256 digest, took the primary Portion of the hexadecimal to transform it to binary, included 3 zeros on the eight digits of your binary and received 00000010011 which interprets to 19 in decimal. https://mysterybookmarks.com/story18777642/little-known-facts-about-bip39-seed-phrase-list