Discussion  - 
 
Is 2013 prime? Obviously not, but can we make it prime by a trick?

A year ago I wrote a blog post claiming that 2012 is prime. The trick was that 2012 is prime when viewed as a number in base 3, base 5, base 13, etc.

I decided to revisit my base trick this year. Is 2013 prime in any base? No. In base n, 2013 represents 2n^3 + n + 3, and this number is composite for every positive n because it can be factored into (n + 1)(2n^2 - 2n + 3).
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+John Cook  Alliterative is interesting, but as a /linguistic/ number property it's dependent on both Base and Language. French linguistic deconstruction of 97 as 4x20+10+7 /Quatre-vingt dix-sept/ would give totally different (and for a guess even scarcer?) alliterative numbers.

I liked Chew's factoid of 2013 being first of a sequence of three 3-factor years, each with the primes being one each of one digit, the next decade, and larger two digit primes. 

MMXIII is the last of a run of roman numerals without a subtractive term. In this new century, this occurs with boring regularity each decade.
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