I took the index with the words, transformed the range to binary, added three zeros, calculated the sha256 digest, took the initial Portion of the hexadecimal to transform it to binary, included 3 zeros to your eight digits of your binary and received 00000010011 which translates to 19 in decimal. https://bookmarkfavors.com/story4345125/the-invalid-bip39-phrase-diaries