I took the index of your words, transformed the quantity to binary, added a few zeros, calculated the sha256 digest, took the initial Component of the hexadecimal to transform it to binary, included a few zeros into the 8 digits with the binary and received 00000010011 which interprets to 19 https://bookmarkblast.com/story18891191/bip39-seed-phrase-mnemonics-generator-an-overview