I took the index of your words, converted the number to binary, added 3 zeros, calculated the sha256 digest, took the 1st Component of the hexadecimal to transform it to binary, additional a few zeros into the eight digits with the binary and obtained 00000010011 which interprets to 19 in https://bookmarkeasier.com/story18882610/little-known-facts-about-bip39-words