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by vanderZwan 1212 days ago
> And it happens to be the case that 7 × 9 = 63, which is almost 64, a power of 2

While the article goes down a different rabbit hole, this also happens to be a neat example of (n-1)(n+1) = n² - 1, where n = 8.

Which is one of those things I haven't managed to find an actual use for but feels like it should have since you can use it with 0xFF (15 × 17), 0xFFFF (255 × 257), and so on.

1 comments

It looks nicer in hexa: 0xFF = 0xF*0x11 and 0xFFFF = 0xFF*0x101