I took the index of your words, transformed the quantity to binary, added 3 zeros, calculated the sha256 digest, took the main A part of the hexadecimal to convert it to binary, extra three zeros to your eight digits with the binary and received 00000010011 which interprets to 19 in https://social4geek.com/story4358738/how-much-you-need-to-expect-you-ll-pay-for-a-good-bip39-definition