Along with a positive integer's Möbius function, it is used extensively in a combinatorial proof of Chen's inversion theorem.
Along with a positive integer's Möbius function, it is used extensively in a combinatorial proof of Chen's inversion theorem. The Levi-Civita permutation symbol is a specialized case (*) of its generalized version, and the base vectors of an orthogonal linear space can be described by its application. The only isotropic tensor of rank-2, an n by n identity matrix can be written in terms of it when the matrix's row and column numbers are represented by its two variables, i and j. FTP, what is this function named for a Polish-born mathematician, which is 1 when both of its variables are equal and 0 otherwise, the discrete analog of a similar "function" named for Dirac?
Along with a positive integer's Möbius function, it is used extensively in a combinatorial proof of Chen's inversion theorem.
{Kronecker Delta} function [prompt on “Kronecker” or “Delta”]