I took the index in the words, transformed the quantity to binary, added 3 zeros, calculated the sha256 digest, took the 1st part of the hexadecimal to transform it to binary, included three zeros for the 8 digits on the binary and obtained 00000010011 which interprets to 19 in decimal. https://bookmarkbells.com/story18907392/facts-about-bip39-seed-phrase-word-list-revealed