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samatman • yesterday at 4:05 PM • 2 replies • view on HN

Me! I'm in!

Most-nearly-prime number under 100 is.... 91.

13 x 7. You've either memorized that or you're going to have fun deciding it's not prime. And if you did times tables up to 13, congratulations, you're special.


Replies

bee_rider • yesterday at 8:20 PM

I think 91 is a strong contender. Sejje has a way of working it out, but of course any small non-prime will have some trick to it.

sejje • yesterday at 7:38 PM

7 is an easy check, not because i did them up to 13.

because 10x7 = 70, i'm left with 21. everyone knows 21 is divisible by 7.