I took the index in the words, transformed the range to binary, included three zeros, calculated the sha256 digest, took the first Portion of the hexadecimal to transform it to binary, included three zeros to the eight digits of your binary and bought 00000010011 which interprets to 19 in decimal. https://bookmarkindexing.com/story18918722/the-fact-about-bip39-seed-phrase-word-list-that-no-one-is-suggesting