My apologies if the question has already been discussed somewhere else, I did not found anything related to unitary fractions with the search tool... It is a nice exercise for hig …

The Erdos-Straus Conjecture says that, for all $n > 1$, there exist positive integers $x,y,z$, such that $\dfrac{4}{n} = \dfrac{1}{x} + \dfrac{1}{y} + \dfrac{1}{z}$. A generalizati …

I had this question bothering me for a while, but I can't come up with a meaningful answer. The problem is the following: Let integers $a_i,b_j\in${$1,\ldots,n$} and $K_1,K_2\in$ …

This is essentially the same as the closed question http://mathoverflow.net/questions/32956/representation-of-rational-numbers-as-the-sum-of-1-k but I hope I can make a case for it …