I took the index of your words, transformed the amount to binary, added a few zeros, calculated the sha256 digest, took the 1st Portion of the hexadecimal to transform it to binary, additional a few zeros to your 8 digits of the binary and bought 00000010011 which translates to 19 https://bookmarkfavors.com/story5202092/a-secret-weapon-for-bip39-words-to-numbers