I took the index of your words, converted the selection to binary, included 3 zeros, calculated the sha256 digest, took the primary Section of the hexadecimal to transform it to binary, included three zeros for the 8 digits with the binary and obtained 00000010011 which translates to 19 in decimal. https://bookmarkoffire.com/story18733466/bip39-seed-phrase-mnemonics-generator-an-overview