I took the index with the words, transformed the range to binary, extra a few zeros, calculated the sha256 digest, took the primary part of the hexadecimal to convert it to binary, extra three zeros to the eight digits in the binary and bought 00000010011 which interprets to 19 in https://bookmarkboom.com/story18822874/a-secret-weapon-for-bip39-words-to-numbers