I took the index of your words, converted the range to binary, included three zeros, calculated the sha256 digest, took the 1st part of the hexadecimal to convert it to binary, additional three zeros for the 8 digits with the binary and bought 00000010011 which translates to 19 in decimal. https://bookmarkplaces.com/story18810278/the-definitive-guide-to-bip39-seed-phrase