I took the index from the words, converted the number to binary, added a few zeros, calculated the sha256 digest, took the first A part of the hexadecimal to convert it to binary, extra 3 zeros for the 8 digits of the binary and obtained 00000010011 which translates to 19 https://bookmarkingace.com/story19021007/little-known-facts-about-bip39-seed-phrase-list