I took the index on the words, transformed the variety to binary, extra three zeros, calculated the sha256 digest, took the main Section of the hexadecimal to transform it to binary, included three zeros into the eight digits on the binary and got 00000010011 which translates to 19 in decimal. https://thejillist.com/story8980135/the-fact-about-valid-bip39-seed-phrase-that-no-one-is-suggesting