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Comment by XCSme | Hacker News Reader

You can do the same thing with pure HTML, just write `2,3,5,7,11,13...`. I am disappointed by the article, was expecting something with CSS `calc()`.

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That's not similar, at all. This is actually removing multiples, as in the sieve of erastosthenes.

It's missing a loop, and the primes are hardcoded into the source code (see the similarity?). You might be mislead by the fact that you also find 'span:nth-child(4n+8)' or 'span:nth-child(6n+12)' (which aren't primes) but those are redundant, and an efficient sieve would skip non primes.

Yes, they are redundant, but there's still no special knowledge of the primes in the file.

The primes are hardcoded into the source the same way that the primes are hardcoded into the sequence of natural numbers. They're there, but the important bit is finding them.

The point is that the file has nothing about the primes in it. 6 and 7 are treated equally, but 7 is displayed and 6 is not.

The file has the first sqrt(1000) primes hardcoded in it.

If you wanted to find the first 100.000 prime numbers, you'd need to add all the prime numbers up to 313 in the css file.

You should look more closely: it doesn't. The CSS selectors are for 2, 3, 4, 5, 6, 7, 8, 9, ..., 32. The most you can say is that it has sqrt(1000) == 32 hardcoded into it, but there are no primes.

Ok, I get it. However, you still need to modify the source code to accomodate for larger inputs.

True dat.

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