What Is Special about the Divisors of 12?
Sunil K. Chebolu, Michael Mayers · Mathematics Magazine · 2013
SummaryWhat is an interesting number theoretic characterization of the divisors of 12 among all positive integers? This paper will provide one answer in terms of modular multiplication tables. We will show that the multiplication table for the ring ℤn [x1, x2, …, xm] has 1's only on the diagonal if and only if n is a divisor of 12.