I took the index of the words, transformed the selection to binary, included a few zeros, calculated the sha256 digest, took the main Element of the hexadecimal to transform it to binary, included 3 zeros to your eight digits of the binary and got 00000010011 which interprets to 19 in https://orangebookmarks.com/story18964695/bip39-phrase-generator-can-be-fun-for-anyone