I took the index of the words, transformed the number to binary, extra three zeros, calculated the sha256 digest, took the primary Component of the hexadecimal to convert it to binary, included 3 zeros to your 8 digits in the binary and received 00000010011 which translates to 19 in decimal. https://madesocials.com/story4249135/bip39-seed-phrase-fundamentals-explained