#P2129. Invariant Polynomials
Invariant Polynomials
Description
Consider a real polynomial P (x, y) in two variables. It is called invariant with respect to the rotation
by an angle α if
for all real x and y.
Let's consider the real vector space formed by all polynomials in two variables of degree not greater than d invariant with respect to the rotation by 2π/n. Your task is to calculate the dimension of this vector space.
You might find useful the following remark: Any polynomial of degree not greater than d can be uniquely written in form
for some real coefficients aij .
Input
The input contains two positive integers d and n separated by one space. It is guaranteed that they are less than one thousand.
Output
Output a single integer M which is the dimension of the vector space described.
2 2
4
Source
Northeastern Europe 2003, Northern Subregion