I took the index of the words, transformed the variety to binary, added three zeros, calculated the sha256 digest, took the main Element of the hexadecimal to transform it to binary, added 3 zeros to the eight digits in the binary and received 00000010011 which translates to 19 in decimal. https://my-social-box.com/story4194124/bip39-phrase-generator-can-be-fun-for-anyone