I took the index of your words, converted the selection to binary, extra 3 zeros, calculated the sha256 digest, took the first Portion of the hexadecimal to transform it to binary, added 3 zeros to your eight digits on the binary and got 00000010011 which interprets to 19 in decimal. https://thegreatbookmark.com/story18859818/the-ultimate-guide-to-bip39-seed-phrase-github