I took the index of your words, transformed the selection to binary, additional 3 zeros, calculated the sha256 digest, took the 1st part of the hexadecimal to convert it to binary, included 3 zeros on the 8 digits in the binary and obtained 00000010011 which translates to 19 in decimal. https://privatebookmark.com/story18885846/the-greatest-guide-to-seed-phrase-bip39