I took the index from the words, transformed the quantity to binary, added three zeros, calculated the sha256 digest, took the primary part of the hexadecimal to transform it to binary, additional a few zeros towards the 8 digits in the binary and obtained 00000010011 which translates to 19 in https://mylittlebookmark.com/story4657098/examine-this-report-on-bip39-mnemonic-phrase-tool