Keep going though. You’ll settle into a rhythm, guaranteed. Unless you keep track in your head or a piece of paper, this strategy starts to fail after about 100 entries. Long term average will be 50%, equivalent of a coin toss.
There is no need to "learn" their predictions (beyond a few at the beginning; edit: and the undetermined cases, I don't know if they choose randomly or deterministically), they are very transparent on how the system works:
"The program keeps a database of each possible combination of 5 presses, and two counters are stored under each entry — one is for every zero that follows the combination, and the other one is for all the ones that follow this combination. So every time you press a key, an entry in the database gets updated. To make a prediction, the program needs only to look up the entry corresponding to the last 5 presses and decide by looking at the counters which key press is more likely to follow."
That was my experience at first as well, but I think the point (that the page doesn't really get across) is that you should start hammering on the keys rather than methodically choosing your next input each time. I did that and saw my score take a nosedive.
Yeah, I do get that and I do think that site demonstrates the point it's making really effectively too. My post was just about the engineer / hacker in me having a bit of fun.
https://i.imgur.com/O3EggFY.png (0% guessed right after 15 key presses)
Here's the sequence I used. I'd be interested if this works for other people too: