I took the index with the words, transformed the variety to binary, extra 3 zeros, calculated the sha256 digest, took the 1st part of the hexadecimal to transform it to binary, included a few zeros to your eight digits with the binary and obtained 00000010011 which translates to 19 in https://bookmarksaifi.com/story18981020/how-much-you-need-to-expect-you-ll-pay-for-a-good-bip39-seed-phrase-mnemonics-generator