I took the index with the words, converted the range to binary, additional three zeros, calculated the sha256 digest, took the 1st Portion of the hexadecimal to transform it to binary, added 3 zeros to the 8 digits of your binary and received 00000010011 which interprets to 19 in decimal. https://bookmarkpagerank.com/story19042596/a-review-of-bip39-phrase-list