I took the index of your words, converted the number to binary, added 3 zeros, calculated the sha256 digest, took the first Section of the hexadecimal to transform it to binary, extra 3 zeros to the 8 digits of your binary and received 00000010011 which interprets to 19 in decimal. https://thebookmarknight.com/story19459783/the-definitive-guide-to-bip39-seed-phrase