I took the index in the words, converted the range to binary, extra three zeros, calculated the sha256 digest, took the primary part of the hexadecimal to transform it to binary, added 3 zeros into the 8 digits with the binary and got 00000010011 which translates to 19 in decimal. https://cruxbookmarks.com/story19078237/how-much-you-need-to-expect-you-ll-pay-for-a-good-bip39-definition