Mathematics Stack Exchange is a question and answer site for people studying math at any level and professionals in related fields. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

How many vertices and edges are there in $K_{i,j}$ and $K_{i,j,k}$?

share|cite|improve this question
Welcome to math.SE, mehtap karabacak: since you are a quite new user, I wanted to let you know a few things about the site. In order to get the best possible answers, it is helpful if you say in what context you encountered the problem, and what your thoughts on it are so far; this will prevent people from telling you things you already know, and help them write their answers at an appropriate level. – draks ... Jun 5 '12 at 22:39
Wikipedia is a useful resource – TMM Jun 5 '12 at 22:40

$K_{i,j}$ is defined as having a group of $i$ vertices and a group of $j$ vertices, with each vertex of the first group connected to each vertex of the second group, and no edges within a group. Is that your definition? If so, there are $i+j$ vertices (just count the two groups) and $ij$ edges as you pick one of the $i$ and one of the $j$ for each edge. How do you define Kijk (is it $K_{i,j,k}$)? If it is similar but with three groups of vertices, the same counting technique will work.

share|cite|improve this answer
Actually i don't know anything about the definition.Yes you understood the question clearly but I need a complete solution for this question. It's not relted to my deparment however i really need that answer.thanks for your interest.. – mehtap karabacak Jun 5 '12 at 23:03
@mehtapkarabacak: if you don't know the definition, there is no way to answer the question. Do you understand the answer for $K_{i,j}$? The Wikipedia page that TMM cites gives a couple pictures that should help. – Ross Millikan Jun 5 '12 at 23:11

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.