I took the index of your words, transformed the number to binary, included a few zeros, calculated the sha256 digest, took the main A part of the hexadecimal to transform it to binary, added 3 zeros into the eight digits of the binary and received 00000010011 which interprets to 19 https://hyperbookmarks.com/story18800906/an-unbiased-view-of-bip39-seed-phrase-github