# Tag Archives: polynomials

## Polynomials and Representations V

It was clear from the earlier articles that n (number of variables ) plays a minimal role in the combinatorics of the symmetric polynomials. Hence, removing the parameter n turns out to be quite convenient; the process gives us the formal ring of symmetric functions. … Continue reading

## Polynomials and Representations IV

Power Sum Polynomials The power sum polynomial is defined as follows: In this case, we do not define , although it seems natural to set As before, for a partition define: Note that we must have above since we have … Continue reading

## Polynomials and Representations III

Complete Symmetric Polynomials Corresponding to the elementary symmetric polynomial, we define the complete symmetric polynomials in to be: For example when , we have: Thus, written as a sum of monomial symmetric polynomials, we have Note that while the elementary symmetric polynomials only go … Continue reading

## Polynomials and Representations II

More About Partitions Recall that a partition is a sequence of weakly decreasing non-negative integers, where appending or dropping ending zeros gives us the same partition. A partition is usually represented graphically as a table of boxes or dots: We will … Continue reading

## Polynomials and Representations I

We have already seen symmetric polynomials and some of their applications in an earlier article. Let us delve into this a little more deeply. Consider the ring of integer polynomials. The symmetric group acts on it by permuting the variables; specifically, … Continue reading

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## Introduction to Ring Theory (7)

Polynomial Rings A polynomial over a ring R is an expression of the form: , where , and . Let’s get some standard terminology out of the way. The element ai is called the coefficient of xi. The largest n for which an ≠ 0 is called … Continue reading

## Power Series and Generating Functions (I): Basics

[ Background required: basic combinatorics, including combinations and permutations. Thus, you should know the formulae and and what they mean. Also, some examples / problems may require calculus. ] Note: this post is still highly relevant to competition-mathematics. 🙂 To … Continue reading

## Symmetric Polynomials (III)

Now we generalise this to n variables: . It’s clear what the corresponding building blocks of symmetric polynomials would be: ; ; ; … . We call these ei‘s the elementary symmetric polynomials in the xi‘s. Note that each ei is the coefficient of Ti in the … Continue reading