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A Prime (Number) Problem

Riddles are little poems or phrases that pose a question that needs answering. Riddles frequently rhyme, but this is not a requirement.


Puzzle ID:#47851
Fun:*** (2.15)
Difficulty:* (0.95)
Submitted By:rlc327us***!




There is a number that fulfills all of the following criteria/rules:

1. It is prime.
2. It is a whole number.
3. It is greater than or equal to 1.
4. If you double it, square it, and add itself to it, you get the same single digit even number answer for each operation.

What is this number?

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Aug 29, 2010

too easy...
Aug 30, 2010

Therefore, N=2.
Aug 30, 2010

Erm... I made a mistake on above comment. It said square. (What was I thinking?) I meant to say:
Therefore, N=2
Aug 30, 2010

I wasn't planning on making it difficult, just exploiting a little mathematical "quirk".
Aug 30, 2010

it wuz pretty easy but it wuz nice to kno (:
Sep 02, 2010

easy but nice one!
Sep 03, 2010

Doubling a number is the same as adding the number to itself. Therefore, the 4th criterion is redundant.
Sep 03, 2010

I'm perfectly aware that the 4th criterion is redundant.
Dec 28, 2010

TOOK me a minute but i got it
Jan 17, 2011

we took that one in KG lol , just type " the only even prime number "

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