I took the index in the words, converted the amount to binary, extra 3 zeros, calculated the sha256 digest, took the 1st part of the hexadecimal to transform it to binary, additional 3 zeros on the 8 digits of the binary and got 00000010011 which interprets to 19 in decimal. https://atozbookmark.com/story18904637/an-unbiased-view-of-bip39-seed-phrase-github