I took the index of your words, transformed the amount to binary, additional 3 zeros, calculated the sha256 digest, took the primary Component of the hexadecimal to transform it to binary, extra 3 zeros on the 8 digits in the binary and obtained 00000010011 which interprets to 19 in decimal. https://bookmarkfavors.com/story4403387/the-definitive-guide-to-bip39-seed-phrase