I took the index of the words, transformed the range to binary, included a few zeros, calculated the sha256 digest, took the initial Component of the hexadecimal to transform it to binary, included three zeros on the eight digits in the binary and bought 00000010011 which translates to 19 in https://one-bookmark.com/story18756566/the-fact-about-valid-bip39-seed-phrase-that-no-one-is-suggesting