I took the index of your words, converted the selection to binary, added three zeros, calculated the sha256 digest, took the main Element of the hexadecimal to transform it to binary, added three zeros into the eight digits in the binary and bought 00000010011 which interprets to 19 in decimal. https://bookmarkity.com/story19029931/bip39-phrase-generator-can-be-fun-for-anyone