Apparently, all IVs have an equal chance of being selected when chosen at random, so if you, for some reason, want to have an HP IV of 24 for whatever reason, then just replace all mentions of 31 HP with 24 HP on the single "flawless" HP section.
In other words (and correct me if I'm wrong here), it doesn't matter how high you want the IV to be, if you're going for a fixed number and the parents have that same fixed number, these are the probabilities.
, a Pokemon AI.
"Strategy without tactics is the slowest route to victory. Tactics without strategy is the noise before defeat." - Sun Tzu