I remember doing combinatorics puzzles and number theory exercises in platforms like Brilliant when I had a bit of free time. All the while learning something. But the last time I tried Brilliant I did not enjoy it as much and I can’t afford it not anyway.
Does anyone have any recommendations of websites (or webrings), apps or games about or that touch on:
- combinatorics puzzles
- modular arithmetic puzzles
- concepts or exercises of number theory
The app Mental Math actually improved my mental math indeed! While division can typically be estimated because it never goes into mixed numbers/fractions, it does eventually go into 5 digits’ worth of all the 4 basic operations; you set the difficulty and climb as you like. I’d never multiplied so accurately in my life, haha.