I took the index in the words, converted the amount to binary, additional 3 zeros, calculated the sha256 digest, took the 1st Element of the hexadecimal to transform it to binary, additional three zeros towards the 8 digits on the binary and obtained 00000010011 which interprets to 19 in decimal. https://bookmarkassist.com/story18766628/5-essential-elements-for-bip39-explained