I took the index of your words, transformed the quantity to binary, extra three zeros, calculated the sha256 digest, took the primary A part of the hexadecimal to convert it to binary, extra three zeros for the eight digits of your binary and acquired 00000010011 which interprets to 19 in https://infopagex.com/story4341073/little-known-facts-about-bip39-seed-phrase-list