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Prime question


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2 Since everything else is not even.

That's the number I had in mind.

... a nice genre of puzzles that asks which of the following choices is unique?

All of them but one has a distinctive feature. The one that doesn't is thus unique.

The only prime number that is not odd is by that criterion the "oddest".

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I've always found 41 to be the most unusual prime, just because of the property that if you start with 41 add 2, then add 4, then add 6, and so on, you will get a prime number for the next 40 numbers:

41, 43, 47, 53, 61, 71, 83, 97...etc...etc...which happens to end at 1681 (41 * 41)

I've always thought that was strange...

ALSO, if you allow NEGATIVE numbers to be prime (in other words -1 and x are the only divisors of x), then -41 is ALSO strange, in that it's the same temperature in Fahrenheit and Celsius (with rounding...yes, I realize -40 is exactly the same...but -41 is pretty darn close...)

So, 41 seems to be the strange number...

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