I took the index from the words, transformed the number to binary, included a few zeros, calculated the sha256 digest, took the initial Element of the hexadecimal to transform it to binary, additional 3 zeros into the 8 digits with the binary and got 00000010011 which translates to 19 in https://socialbaskets.com/story4604440/considerations-to-know-about-bip39-seed-phrase-generator