I took the index of your words, converted the variety to binary, added 3 zeros, calculated the sha256 digest, took the first Section of the hexadecimal to convert it to binary, added 3 zeros into the eight digits on the binary and got 00000010011 which translates to 19 in decimal. https://monobookmarks.com/story18901043/not-known-factual-statements-about-bip39-explained