I took the index on the words, converted the selection to binary, additional 3 zeros, calculated the sha256 digest, took the first Portion of the hexadecimal to transform it to binary, added 3 zeros to your 8 digits in the binary and received 00000010011 which interprets to 19 in decimal. https://bookmarkzap.com/story19045960/the-fact-about-bip39-seed-phrase-word-list-that-no-one-is-suggesting