I took the index of your words, transformed the number to binary, included 3 zeros, calculated the sha256 digest, took the primary Section of the hexadecimal to convert it to binary, included 3 zeros to the 8 digits on the binary and acquired 00000010011 which translates to 19 in decimal. https://bookmarkilo.com/story19351930/little-known-facts-about-bip39-seed-phrase-list