I took the index in the words, transformed the quantity to binary, extra 3 zeros, calculated the sha256 digest, took the main A part of the hexadecimal to transform it to binary, extra 3 zeros into the 8 digits from the binary and received 00000010011 which translates to 19 in https://keybookmarks.com/story18989184/5-essential-elements-for-bip39-explained