I took the index in the words, converted the quantity to binary, additional 3 zeros, calculated the sha256 digest, took the primary Element of the hexadecimal to transform it to binary, added three zeros to your 8 digits of the binary and got 00000010011 which interprets to 19 in decimal. https://sb-bookmarking.com/story18994322/the-ultimate-guide-to-bip39-seed-phrase-mnemonics-generator