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We give names to the sets of numbers called Primes and Composites. Is there a name for the number 1, in this context, seeing it is neither a Prime or Composite?

Paul
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    $1$ (and $-1$) are called units. A prime can be defined as a number $p$ that is not a unit and is such that for any factorization $p=ab$ either $a$ or $b$ is a unit. Elements which are neither prime nor units are composite. – TravisJ Apr 29 '15 at 00:24
  • This is weird but... 1 is a composite of itself, 111...*1 = 1 so why is not considered as a special case of composite number? – iadvd Apr 29 '15 at 03:33
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    @iadvd - because $1$ is not prime. – Joffan Apr 29 '15 at 19:06
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    @Joffan true! :) it leads also to the typical discussion about 1 being prime or not (which is not, I know...) – iadvd Apr 30 '15 at 00:54

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