I took the index on the words, converted the range to binary, added 3 zeros, calculated the sha256 digest, took the very first Element of the hexadecimal to transform it to binary, extra three zeros for the 8 digits with the binary and got 00000010011 which interprets to 19 in https://sb-bookmarking.com/story19094208/considerations-to-know-about-bip39-word-list-pdf