I took the index on the words, transformed the range to binary, additional 3 zeros, calculated the sha256 digest, took the main Section of the hexadecimal to convert it to binary, added three zeros towards the 8 digits in the binary and got 00000010011 which translates to 19 in decimal. https://socialskates.com/story19954042/the-ultimate-guide-to-bip39-seed-phrase-github